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TABLE OF CONTENTS
INDEX TO FINANCIAL STATEMENTS

Table of Contents

As filed with the Securities and Exchange Commission on March 27, 2017

Registration No. 333-            

 

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549



FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933



Antero Resources Midstream Management LLC
to be converted as described herein into a limited partnership named

Antero Midstream GP LP
(Exact Name of Registrant as Specified in its Charter)



Delaware
(State or other jurisdiction of
Incorporation or Organization)
  4922
(Primary Standard Industrial
Classification Code Number)
  61-1748605
(IRS Employer
Identification Number)

1615 Wynkoop Street
Denver, Colorado 80202
(303) 357-7310

(Address, Including Zip Code, and Telephone Number, Including
Area Code, of Registrant's Principal Executive Offices)



Glen C. Warren, Jr.
1615 Wynkoop Street
Denver, Colorado 80202
(303) 357-7310

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)



Copies to:

William N. Finnegan IV
Ryan J. Maierson
Latham & Watkins LLP
811 Main Street, Suite 3700
Houston, Texas 77002
(713) 546-5400

 

David P. Oelman
Julian J. Seiguer
Vinson & Elkins L.L.P.
1001 Fannin Street, Suite 2500
Houston, Texas 77002
(713) 758-2222



Approximate date of commencement of proposed sale to the public:
As soon as practicable after this Registration Statement becomes effective.

           If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box.    o

           If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. Please read the definition of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer o   Accelerated filer o   Non-accelerated filer ý
(Do not check if a
smaller reporting company)
  Smaller reporting company o

CALCULATION OF REGISTRATION FEE

       
 
Title of Each Class of Securities to be Registered
  Amount to be
Registered(1)(2)

  Amount of
Registration Fee

 

Common shares representing limited partner interests

  $100,000,000   $11,590

 

(1)
Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(o) under the Securities Act of 1933, as amended.

(2)
Includes common shares issuable upon exercise of the underwriters' option to purchase additional common shares.

           The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8 (a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

   


Table of Contents

The information in this preliminary prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PROSPECTUS Subject to Completion,
dated March 27, 2017



GRAPHIC

              Common Shares
Representing Limited Partner Interests



This is the initial public offering of our common shares representing limited partner interests. We are a Delaware limited partnership that will elect to be treated as a corporation for U.S. federal income tax purposes. We expect the initial public offering price of our common shares to be between $                and $               per common share.

Before this offering, there has been no public market for our common shares. We have applied to list our common shares on the New York Stock Exchange under the symbol "AMGP." We are an "emerging growth company" as that term is used in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act.

We own the general partner of Antero Midstream Partners LP (NYSE: AM) ("Antero Midstream") and all of the incentive distribution rights ("IDRs") in Antero Midstream. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on its IDRs. Antero Midstream is a publicly traded master limited partnership that owns, operates and develops midstream energy infrastructure primarily to service Antero Resources Corporation's (NYSE: AR) ("Antero Resources") rapidly increasing production and completion activity in the Appalachian Basin's Marcellus Shale and Utica Shale located in West Virginia and Ohio.

All of the common shares being sold in this offering are being offered by the selling shareholder. We will not receive any of the proceeds from this offering. Upon completion of this offering, the selling shareholder will own                             of our common shares, or approximately          % of our outstanding common shares.

Investing in our common shares involves risks. Please read "Risk Factors" beginning on page 29.

These risks include the following:

    Our cash flow will be entirely dependent upon the ability of Antero Midstream to make cash distributions on its IDRs.

    Our right to receive distributions paid by Antero Midstream on its IDRs may be limited or modified by our general partner without the consent of our shareholders, which may reduce cash distributions to you.

    Our shareholders will not elect or have the power to remove our general partner and will not vote in the election of our general partner's directors. Upon the completion of this offering, certain of our existing owners (the "Sponsors") will own a sufficient number of our common shares to allow them to prevent the removal of our general partner.

    You will experience immediate and substantial dilution of $               per common share in the net tangible book value of your common shares.

    Conflicts of interest may arise as a result of our organizational structure and the relationships among us, Antero Midstream, our respective general partners, Antero Resources and other affiliated entities.

    The tax treatment of Antero Midstream depends on its status as a partnership for U.S. federal income tax purposes, as well as it not being subject to a material amount of entity-level taxation by individual states. If the Internal Revenue Service ("IRS") were to treat Antero Midstream as a corporation or Antero Midstream becomes subject to additional amounts of entity-level taxation for state or foreign tax purposes, it would reduce the amount of cash available for distribution to us.

 
 
Per Common Share
 
Total

Initial public offering price

  $              $           

Underwriting discount(1)

  $              $           

Proceeds to the selling shareholder

  $              $           


(1)
We refer you to "Underwriting" beginning on page 237 of this prospectus for additional information regarding underwriting compensation.

The selling shareholder has granted the underwriters a 30-day option to purchase up to an additional                           common shares on the same terms and conditions as set forth above if the underwriters sell more than                           common shares in this offering. We will not receive any proceeds from any common shares to be sold by the selling shareholder upon any exercise of the underwriters' option to purchase additional common shares.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The underwriters expect to deliver the common shares on or about                           , 2017.



Morgan Stanley   Barclays   J.P. Morgan

   

Prospectus dated                           , 2017


Table of Contents

[Inside Cover Art]


Table of Contents


TABLE OF CONTENTS

 
  Page  

SUMMARY

    1  

Antero Midstream GP LP

    1  

The Appalachian Basin

    5  

Antero Resources Corporation

    6  

Antero Midstream Partners LP

    7  

Recent Developments

    9  

Antero Midstream's Business Strategies

    10  

Antero Midstream's Competitive Strengths

    11  

Organizational Structure

    14  

Principal Executive Offices

    16  

Risk Factors

    17  

Summary of Conflicts of Interest and Duties

    18  

Implications of Being an Emerging Growth Company

    19  

The Offering

    21  

Summary Historical Financial Data

    25  

RISK FACTORS

    29  

Risks Inherent in an Investment in Us

    29  

Risks Related to Conflicts of Interest

    39  

Risks Related to Antero Midstream's Business

    42  

Tax Risks

    59  

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

    61  

ORGANIZATIONAL STRUCTURE

    63  

USE OF PROCEEDS

    66  

CAPITALIZATION

    67  

DILUTION

    68  

OUR CASH DISTRIBUTION POLICY AND RESTRICTIONS ON DISTRIBUTIONS

    69  

General

    69  

Series B Units

    72  

Our Initial Cash Distribution

    73  

Overview of Presentation

    74  

Unaudited Pro Forma Available Cash to Pay Distributions for the Years Ended December 31, 2015 and 2016

    75  

Estimated Cash Available for Distribution Based upon Adjusted EBITDA of Antero Midstream Partners LP

    76  

Assumptions and Considerations

    79  

Distributions from Antero Midstream Partners LP to Antero IDR Holdings LLC and Antero Midstream GP LP

    84  

HOW WE MAKE CASH DISTRIBUTIONS

    85  

General

    85  

Our Sources of Cash

    85  

Shares

    86  

General Partner Interest

    86  

Distributions of Cash Upon Liquidation

    86  

SELECTED HISTORICAL FINANCIAL DATA

    87  

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

    88  

Overview

    88  

Commodity Price Environment

    88  

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Table of Contents

 
  Page  

Our Sources of Revenue

    88  

Financial Presentation

    89  

Our Cash Distributions

    89  

Our Results of Operations

    89  

Our Liquidity and Capital Resources

    90  

Our Critical Accounting Policies and Estimates

    90  

Our Off-Balance Sheet Arrangements

    91  

Antero Midstream's Results of Operations

    91  

Antero Midstream's Sources of Revenue

    92  

How Antero Midstream Evaluates Antero Midstream's Operations

    93  

Antero Midstream's Principal Components of Cost Structure

    94  

Items Affecting Comparability of Antero Midstream's Financial Results

    95  

Antero Midstream's Results of Operations

    97  

Antero Midstream's Capital Resources and Liquidity

    105  

Antero Midstream's Non-GAAP Financial Measures

    109  

Antero Midstream's Critical Accounting Policies and Estimates

    110  

New Accounting Pronouncements Affecting Antero Midstream

    112  

Antero Midstream's Off-Balance Sheet Arrangements

    112  

OUR BUSINESS

    113  

General

    113  

How Our Partnership Agreement Terms Differ from Those of Other Publicly Traded Partnerships

    117  

Legal Proceedings

    117  

Employees

    117  

Antero Resources Corporation

    118  

Antero Midstream Partners LP

    119  

Antero Midstream's Business Strategies

    121  

Antero Midstream's Competitive Strengths

    122  

Antero Midstream's Contractual Arrangements with Antero Resources

    125  

Antero Resources' Existing Third-Party Commitments

    127  

Antero Midstream's Title to Properties

    127  

Seasonality

    128  

Antero Midstream's Customers

    128  

Antero Midstream's Competition

    128  

Regulation of Antero Midstream's Operations

    128  

Regulation of Environmental and Occupational Safety and Health Matters

    132  

Antero Midstream's Employees

    137  

MANAGEMENT

    138  

Our Management and Governance

    138  

Directors and Executive Officers of Our General Partner and Antero Midstream

    139  

Designation of Directors

    141  

Our Board Committees

    141  

Our Long-Term Incentive Plan

    142  

Compensation of Our Officers

    145  

Compensation of Our Directors

    145  

EXECUTIVE COMPENSATION

    146  

Executive Compensation

    146  

Compensation Discussion and Analysis

    146  

Overview

    146  

Executive Summary

    147  

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  Page  

Implementing the Company's Compensation Program Objectives

    148  

Competitive Benchmarking

    149  

Elements of Compensation

    151  

Other Benefits

    158  

2017 Changes to Base Salaries and Annual Incentive Plan

    159  

Employment, Severance or Change in Control Agreements

    159  

Other Matters

    160  

Summary Compensation Table

    162  

Grant of Plan-Based Awards for Fiscal Year 2016

    164  

Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table

    165  

Option Exercises and Stock Vested in Fiscal Year 2016

    169  

Pension Benefits

    169  

Nonqualified Deferred Compensation

    169  

Payments Upon Termination or Change in Control

    170  

Potential Payments Upon Termination or Change in Control Table for Fiscal Year 2016

    173  

PRINCIPAL AND SELLING SHAREHOLDERS

    175  

Antero Midstream GP LP

    175  

Antero Midstream Partners LP

    176  

Antero Resources Corporation

    176  

CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

    178  

Our Related Party Transactions

    178  

Procedures for Review, Approval and Ratification of Transactions with Related Persons

    181  

Antero Midstream's Related Party Transactions with Antero Resources

    181  

CONFLICTS OF INTEREST AND FIDUCIARY DUTIES

    187  

Conflicts of Interest

    187  

Potential for Conflicts

    187  

Conflicts Resolution

    189  

Fiduciary Duties of Our General Partner

    190  

Indemnification Matters

    192  

DESCRIPTION OF OUR COMMON SHARES

    193  

Redemption Right

    193  

Transfer of Common Shares

    193  

Transfer Agent and Registrar

    194  

COMPARISON OF RIGHTS OF HOLDERS OF OUR COMMON SHARES AND ANTERO MIDSTREAM'S COMMON UNITS

    195  

DESCRIPTION OF OUR PARTNERSHIP AGREEMENT

    197  

Organization and Duration

    197  

Purpose

    197  

Cash Distributions

    198  

Capital Contributions

    198  

Applicable Law; Forum, Venue and Jurisdiction

    198  

Reimbursement of Partnership Litigation Costs

    198  

Limited Liability

    199  

Limited Voting Rights

    200  

Transfer of Ownership Interests in Our General Partner

    200  

Issuance of Additional Securities

    201  

Amendments to Our Partnership Agreement

    201  

Merger, Sale or Other Disposition of Assets

    203  

Termination or Dissolution

    204  

Liquidation and Distribution of Proceeds

    204  

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  Page  

Withdrawal or Removal of the General Partner

    204  

Transfer of General Partner Interest

    205  

Change of Management Provision

    205  

Limited Call Right

    205  

Meetings; Voting

    205  

Status as Limited Partner

    206  

Non-Citizen Assignees; Redemption

    206  

Indemnification

    207  

Reimbursement of Expenses

    207  

Books and Reports

    207  

Right to Inspect Our Books and Records

    208  

ANTERO MIDSTREAM PARTNERS LP'S CASH DISTRIBUTION POLICY

    209  

Cash Distribution Policy

    209  

Operating Surplus and Capital Surplus

    209  

Capital Expenditures

    210  

General Partner Interest

    211  

Incentive Distribution Rights

    211  

Effect of Issuance of Additional Units

    212  

Distributions From Operating Surplus

    213  

Distributions from Capital Surplus

    213  

Adjustment to the Minimum Quarterly Distribution and Target Distribution Levels

    213  

Distribution of Cash Upon Liquidation of Antero Midstream

    214  

MATERIAL PROVISIONS OF THE PARTNERSHIP AGREEMENT OF ANTERO MIDSTREAM PARTNERS LP

    217  

Organization and Duration

    217  

Purpose

    217  

Cash Distributions

    217  

Capital Contributions

    217  

Voting Rights

    217  

Applicable Law; Forum, Venue and Jurisdiction

    219  

Reimbursement of Antero Midstream Litigation Costs

    219  

Issuance of Additional Interests

    219  

Amendment of the Antero Midstream Partnership Agreement

    220  

Merger, Consolidation, Conversion, Sale or Other Disposition of Assets

    222  

Dissolution

    223  

Liquidation and Distribution of Proceeds

    223  

Withdrawal or Removal of Antero Midstream's General Partner

    224  

Transfer of General Partner Interest

    224  

Transfer of Ownership Interests in the General Partner

    225  

Transfer of Incentive Distribution Rights

    225  

Change of Management Provisions

    225  

Limited Call Right

    226  

Non-Taxpaying Holders; Redemption

    226  

Non-Citizen Assignees; Redemption

    226  

Meetings; Voting

    227  

Voting Rights of Incentive Distribution Rights

    228  

Status as Limited Partner

    228  

Indemnification

    228  

Reimbursement of Expenses

    229  

Books and Reports

    229  

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  Page  

Right to Inspect Antero Midstream's Books and Records

    229  

Registration Rights

    230  

SHARES ELIGIBLE FOR FUTURE SALE

    231  

Rule 144

    231  

Issuance of Additional Securities

    231  

Registration Rights Agreement

    232  

Lock-Up Agreements

    232  

MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS

    233  

Definition of a Non-U.S. Holder

    234  

Distributions

    234  

Sale or Other Taxable Disposition

    235  

Information Reporting and Backup Withholding

    236  

Additional Withholding Tax on Payments Made to Foreign Accounts

    236  

INVESTMENT IN ANTERO MIDSTREAM MANAGEMENT LLC BY EMPLOYEE BENEFIT PLANS

    237  

General Fiduciary Matters

    237  

Prohibited Transaction Issues

    238  

Plan Asset Issues

    238  

UNDERWRITING

    239  

Pricing of the Offering

    241  

Directed Share Program

    241  

LEGAL MATTERS

    243  

EXPERTS

    243  

WHERE YOU CAN FIND MORE INFORMATION

    243  

INDEX TO FINANCIAL STATEMENTS

    F-1  

APPENDIX A AGREEMENT OF LIMITED PARTNERSHIP OF ANTERO MIDSTREAM GP LP

    A-1  

APPENDIX B GLOSSARY OF SELECTED TERMS

    B-1  



        You should rely only on the information contained or incorporated by reference in this prospectus and any free writing prospectus prepared by or on behalf of us or information to which we have referred you. We, the selling shareholder and the underwriters have not authorized anyone to provide you with additional or different information from that contained or incorporated by reference in this prospectus or any free writing prospectus. If anyone provides you with additional, different or inconsistent information you should not rely on it. We, the selling shareholder and the underwriters have not authorized making an offer to sell these securities in any jurisdiction where an offer or sale is not permitted. Unless otherwise indicated, you should assume that the information appearing in this prospectus is accurate as of the date on the front cover of this prospectus only, regardless of the time of delivery of this prospectus or any sale of common shares offered hereby.

        This prospectus contains forward-looking statements that are subject to a number of risks and uncertainties, many of which are beyond our control. Please read "Risk Factors" and "Cautionary Statement Regarding Forward-Looking Statements."


Industry and Market Data

        The market data and certain other statistical information used throughout this prospectus are based on independent industry publications, government publications and other published independent sources we believe to be reliable. Some data is also based on our good faith estimates. The industries in which Antero Resources, Antero Midstream and we operate are subject to a high degree of uncertainty and risk

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due to a variety of factors, including those described in the section entitled "Risk Factors." These and other factors could cause Antero Resources', Antero Midstream's and our results to differ materially from those expressed in these publications.


Reserve Information

        The estimates of Antero Resources' net proved, probable and possible reserves as of December 31, 2016 included in this prospectus are based on evaluations prepared by Antero Resources' internal reserve engineers, which have been audited by DeGolyer and MacNaughton, Antero Resources' independent reserve engineers, using SEC pricing and assuming ethane rejection.


Basis of Presentation

        Certain monetary amounts, percentages and other figures included in this prospectus have been subject to rounding adjustments. Percentage amounts included in this prospectus have not in all cases been calculated on the basis of such rounded figures but on the basis of such amounts prior to rounding. For this reason, percentage amounts in this prospectus may vary from those obtained by performing the same calculations using the figures in our consolidated financial statements. Certain other amounts that appear in this prospectus may not sum due to rounding.


Certain Assumptions and Terms Used in this Prospectus

        Except as otherwise indicated, the information presented in this prospectus assumes (i) an initial public offering price of $            per common share (the midpoint of the price range set forth on the cover of this prospectus) and (ii) that the underwriters do not exercise their option to purchase additional common shares from the selling shareholder. All references in this prospectus to:

    "AMGP," "our," "we," "us" and like terms refer (i) when used in the present tense or prospectively, to Antero Midstream GP LP and its subsidiaries following the completion of the Reorganization and (ii) when used in a historical context, to our Predecessor;

    "AMP GP" refer to Antero Midstream Partners GP LLC, which will be the sole general partner of Antero Midstream following the completion of the Reorganization;

    "Antero Investment" or the "selling shareholder" refer to Antero Resources Investment LLC, which owns 100% of the membership interest in us immediately prior to this offering and will be liquidated following this offering;

    "Antero Midstream" refer to Antero Midstream Partners LP (NYSE: AM) and its subsidiaries collectively or, if the context requires, to Antero Midstream Partners LP individually;

    "Antero Resources" refer to Antero Resources Corporation (NYSE: AR) and its subsidiaries collectively or, if the context requires, to Antero Resources Corporation individually;

    "ARI Members" refer to the Sponsors and the other entities and individuals that collectively (i) own 100% of the membership interest in Antero Investment immediately prior to its liquidation in connection with the Reorganization and (ii) will own            of our common shares (representing a      % limited partner interest in us) following the completion of this offering and the Reorganization;

    our "common shares" refer to the common shares representing limited partner interests in us, and references to our "shareholders" refer to the persons holding such limited partner interests;

    our "general partner" or "AMGP GP" refer to AMGP GP LLC, our sole general partner;

    "IDRs" refer to the incentive distribution rights representing limited partner interests in Antero Midstream;

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    "IDR LLC" refer to Antero IDR Holdings LLC, which owns all of the IDRs;

    "IDR LLC unit" refer collectively to the Series A Units and Series B Units;

    "Joint Venture" refer to the joint venture entered into on February 6, 2017 between Antero Midstream and MarkWest Energy Partners, L.P. ("MarkWest"), a wholly owned subsidiary of MPLX, LP ("MPLX"), to develop processing and fractionation assets in Appalachia;

    our "partnership agreement" refer to the Agreement of Limited Partnership of Antero Midstream GP LP in the form of Appendix A to this prospectus to be adopted in connection with the completion of this offering;

    our "Predecessor" refer to Antero Resources Midstream Management LLC, which is the sole general partner of Antero Midstream prior to the Reorganization;

    "Reorganization" refer to the reorganization transactions described in this prospectus under "Organizational Structure," which will be completed simultaneously with the completion of this offering;

    "Series A Units" refer to the capital interests in IDR LLC designated as Series A Units;

    "Series B Holders" refer to the senior members of Antero Midstream's management team that hold Series B Units;

    "Series B Units" refer to the profits interests in IDR LLC designated as Series B Units;

    "Sponsors" refer to the entities and individuals that collectively own 100% of the membership interest in our general partner and, following the completion of this offering and the Reorganization, will own            of our common shares (representing a            % limited partner interest in us); and

    "Water Acquisition" refer to Antero Resources' contribution of (i) all of the outstanding limited liability company interests of Antero Water LLC ("Antero Water") to Antero Midstream and (ii) all of the assets, contracts, rights, permits and properties owned or leased by Antero Resources and used primarily in connection with the construction, ownership, operation, use or maintenance of the advanced wastewater treatment complex under construction in Doddridge County, West Virginia (the "Antero Clearwater Facility"), by Antero Treatment LLC ("Antero Treatment"), a wholly owned subsidiary of Antero Midstream.

        Except as otherwise indicated, all discussions in this prospectus regarding ownership interests in us or IDR LLC assume no redemption of Series B Units held by the Series B Holders. Please see "Summary—Organizational Structure" for a diagram depicting our organizational structure immediately following the completion of this offering (assuming the underwriters' option to purchase additional common shares is not exercised).

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SUMMARY

        This summary provides a brief overview of information contained elsewhere in this prospectus. You should read this entire prospectus and the documents to which we refer you before making an investment decision. You should carefully consider the information set forth under "Risk Factors," "Cautionary Statement Regarding Forward-Looking Statements" and "Management's Discussion and Analysis of Financial Condition and Results of Operations," as well as the historical financial statements and the related notes to those financial statements included elsewhere in this prospectus. The information presented in this prospectus assumes an initial public offering price of $            per common share (the midpoint of the price range set forth on the cover page of this prospectus) and, unless otherwise indicated, that the underwriters' option to purchase additional common shares is not exercised.

        For a definition of certain terms used in this prospectus, please read "Certain Assumptions and Terms Used in this Prospectus" beginning on page vi. In addition, we include a glossary of certain commonly used terms in the oil and natural gas industry used in this prospectus as Appendix B.


Antero Midstream GP LP

        We are a Delaware limited partnership that will elect to be treated as a corporation for U.S. federal income tax purposes. We own the general partner of Antero Midstream Partners LP (NYSE: AM) ("Antero Midstream") and all of the incentive distribution rights ("IDRs") in Antero Midstream. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on the IDRs. Antero Midstream is a growth-oriented master limited partnership 59% owned by Antero Resources Corporation (NYSE: AR) ("Antero Resources") that was formed to own, operate and develop midstream energy infrastructure primarily to service Antero Resources' rapidly increasing production and completion activity in the Appalachian Basin's Marcellus Shale and Utica Shale located in West Virginia and Ohio. We believe that Antero Midstream's strategically located assets and integrated relationship with Antero Resources position it to be a leading Appalachian midstream provider across the midstream value chain. Through our ownership interest in Antero IDR Holdings LLC ("IDR LLC"), our subsidiary, we receive cash distributions from Antero Midstream on the IDRs. We expect these cash distributions to increase substantially over time as Antero Midstream executes its business strategy.

        Antero Resources is the second largest natural gas and the largest NGL producer in Appalachia and the eighth largest natural gas producer in North America based on fourth quarter 2016 production volumes. Antero Resources holds over 616,000 net acres as of December 31, 2016 in the highly prolific southwestern core of the Marcellus Shale in northwest West Virginia and southwestern Pennsylvania and the core of the Utica Shale in southern Ohio. Antero Resources believes that the Marcellus and Utica Shales are two of the premier North American shale plays. Since January 2010, the combined natural gas production in the Marcellus and Utica Shales has increased by over 18 Bcf/d from 4 Bcf/d in 2010 to 22 Bcf/d in 2016 and currently represents over 30% of total U.S. natural gas production. Additionally, according to Wood Mackenzie, Marcellus and Utica Shale production is expected to grow to 37 Bcf/d by 2021, which would account for 40% of total expected U.S. natural gas production.

        Since 2010, Antero Resources has drilled and completed 529 horizontal wells in the Marcellus Shale and 150 horizontal wells in the Utica Shale with a 100% drilling success rate. As of December 31, 2016, Antero Resources reported estimated net proved reserves of 15.4 Tcfe and its net proved, probable and possible ("3P") drilling inventory consisted of 3,630 identified potential horizontal well locations. Antero Resources' 2017 drilling and completion budget of $1.3 billion is expected to fund the completion of 170 wells, operating an average of seven drilling rigs, including four in the Marcellus Shale and three in the Utica Shale. For 2017, Antero Resources has publicly announced net daily production guidance of approximately 2.2 Bcfe/d, which represents an 85% compound annual growth rate since 2010. Antero

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Resources is Antero Midstream's largest customer and accounted for substantially all of Antero Midstream's revenues for the year ended December 31, 2016.

        Antero Midstream's assets consist of gathering pipelines, compressor stations, processing and fractionation plants and water handling and treatment infrastructure, through which Antero Midstream provides gathering, compression, processing, fractionation and integrated water services, including fresh water delivery services and other fluid handling services. These services are provided to Antero Resources under long-term, fixed-fee contracts, limiting Antero Midstream's direct exposure to commodity price volatility. As of December 31, 2016, all of Antero Resources' approximate 702,000 gross acres (616,000 net acres) are dedicated to Antero Midstream for gathering, compression and water services, except for approximately 173,000 gross acres subject to third-party gathering and compression commitments. Under its agreements with Antero Midstream, and subject to any pre-existing dedications or other third-party commitments, Antero Resources has dedicated to Antero Midstream all of its current and future acreage in West Virginia, Ohio and Pennsylvania for gathering and compression services and all of its acreage within defined services areas in West Virginia and Ohio for water services. Antero Midstream also has certain rights of first offer with respect to gathering, compression, processing and fractionation services and water services for acreage located outside of the existing dedicated areas. The gathering and compression and water services agreements each have a 20-year initial term and are subject to automatic annual renewal after the initial term. Additionally, in connection with Antero Midstream's entry into a joint venture with MarkWest Energy Partners, L.P., a wholly owned subsidiary of MPLX, LP, to develop processing and fractionation assets in Appalachia, Antero Midstream released to the Joint Venture its right to provide certain processing and fractionation services on 195,000 gross acres held by Antero Resources in Ritchie, Tyler and Wetzel Counties in West Virginia. The processing and fractionation arrangements are underpinned by long-term agreements subject to automatic annual renewal after the initial term.

        We own the IDRs in Antero Midstream through our interest in IDR LLC, which we control as the managing member. IDR LLC has issued all of its capital interests to us in the form of Series A Units and has issued Series B Units, representing profits interests that vest ratably over a three-year period, to certain senior members of Antero Midstream's management team. Through our interest in IDR LLC, we receive 100% of the first $7.5 million of quarterly cash distributions paid by Antero Midstream on the IDRs. The Series B Holders will receive up to 6% of all quarterly cash distributions in excess of $7.5 million paid by Antero Midstream on the IDRs and we will receive the remainder of such distributions. Based on Antero Midstream's existing incentive distribution structure, the IDRs are entitled to receive increasing percentages of Antero Midstream's quarterly cash distributions to the extent those distributions exceed $0.1955 per unit per quarter, including 50% of all incremental cash distributed by Antero Midstream per quarter after Antero Midstream has distributed $0.2550 per unit in respect of its common units for that quarter. We in turn will pay our shareholders, on a quarterly basis, distributions equal to the cash distributions we receive on the IDRs, less distributions paid to or reserved for the Series B Holders, taxes and other expenses.

        We believe that as Antero Midstream continues to execute on its business objective to consistently increase its distributions to its unitholders over time, Antero Midstream will in turn substantially increase its cash distributions on the IDRs. Since its initial public offering, Antero Midstream has grown its quarterly distribution 65% from its minimum quarterly distribution of $0.17 per unit ($0.68 per unit on an annualized basis) for the quarter ended December 31, 2014 (the initial quarter for which Antero Midstream paid a quarterly cash distribution) to $0.28 per unit ($1.12 per unit on an annualized basis) for the quarter ended December 31, 2016. For 2017, Antero Midstream has publicly announced distribution growth guidance of 28% to 30% as compared to 2016. Antero Midstream's ability to consistently grow its cash distributions is driven by a combination of Antero Resources' production growth and Antero Midstream's accretive build-out of additional midstream infrastructure to service that production growth.

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        Based on Antero Midstream's quarterly distribution of $0.28 per unit for the fourth quarter of 2016 and the number of outstanding Antero Midstream units as of February 1, 2017, the record date for such distribution, Antero Midstream's aggregate quarterly cash distributions in respect of the IDRs were approximately $7.5 million for that quarter. The graph below illustrates the growth in Antero Midstream's historical quarterly distributions per unit and the aggregate distributions paid by Antero Midstream on all of its partnership interests, including the IDRs, during each of the periods presented.

GRAPHIC


(1)
Antero Midstream's historical distributions are not necessarily indicative of its ability to distribute similar amounts or continue to increase such distributions in the future. Please read "Risk Factors—Risks Related to Antero Midstream's Business" for a description of the risks that could cause Antero Midstream's future distributions to differ materially from its historical distributions.

(2)
Represents quarterly distributions per unit declared and paid since the completion of Antero Midstream's initial public offering on November 10, 2014 (the "Antero Midstream IPO").

(3)
Represents the aggregate quarterly cash value of distributions declared and paid on Antero Midstream's common and subordinated units and IDRs since the Antero Midstream IPO.

(4)
Antero Midstream paid a cash distribution of $0.0943 per unit for the partial quarter ended December 31, 2014, the quarter in which it completed the Antero Midstream IPO. This amount represented the prorated minimum quarterly distribution of $0.17 per unit, or $0.68 per unit on an annualized basis.

(5)
On February 9, 2017, in connection with the payment of the fourth quarter 2016 quarterly distribution to Antero Midstream's unitholders of record on February 1, 2017, all of the subordinated units in Antero Midstream converted into common units on a one-for-one basis.

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        The following graph presents the impact on aggregate cash available for distribution resulting from potential changes in Antero Midstream's 2016 annualized distribution of $1.03 per unit. The potential distribution increases presented are consistent with Antero Midstream's 2017 annual distribution growth guidance of 28% to 30%. This information is presented for illustrative purposes only and is not intended to be a prediction of our actual future performance.

GRAPHIC

Antero Midstream Hypothetical Distribution per Unit

  $ 0.68   $ 0.80   $ 1.03   $ 1.33   $ 1.71   $ 2.21   $ 2.85  

AMGP Hypothetical Distribution per Common Share(3)

  $     $     $     $     $     $     $    

% Growth

         %        %        %        %        %        %        %

(1)
Amounts shown in the graph above represent our potential cash available for distribution assuming different hypothetical distributions by Antero Midstream on its outstanding common units. Per-unit amounts shown are based on 185,793,884 common units outstanding as of February 28, 2017. The issuance of additional common units by Antero Midstream, including common units issued from time to time under Antero Midstream's at-the-market equity offering program, may decrease cash distributions by Antero Midstream on its IDRs, which, in turn, would reduce our cash available for distribution.

(2)
AMGP cash available for distribution based on total IDR distributions from Antero Midstream, less (i) distributions to be paid to or reserved for Series B Holders, (ii) general and administrative expenses and (iii) U.S. federal and state income taxes (assuming a 38% effective income tax rate).

(3)
Represents our cash available for distribution, divided by an assumed                    common shares outstanding.

        As demonstrated in the graph above, we expect our cash available for distribution to grow at a multiple of the underlying rate of growth of Antero Midstream's distributions on its units. Accordingly, our primary business objective is to increase our cash available for distribution to our shareholders through Antero Midstream's execution of its business strategy. The impact of changes in Antero Midstream's per unit cash distribution levels on our cash available for distribution will vary depending on several factors, including the number of outstanding Antero Midstream common units on the record date for cash distributions. In addition, the level of our cash available for distribution is subject to risks associated with the underlying business of, and an investment in, Antero Midstream. Please read "Risk Factors—Risks Related to Antero Midstream's Business." If one or more of these risks were to occur, Antero Midstream's cash available for distribution would decrease, which would decrease the distributions paid to IDR LLC

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and, in turn, the distributions IDR LLC pays to us. Please read "Risk Factors—Risks Inherent in an Investment in Us—A reduction in Antero Midstream's distributions will disproportionately affect the amount of cash distributions on the IDRs." Such a decrease would reduce our cash available for distribution and the distributions we pay our shareholders.

        We expect our quarterly cash distributions for the twelve-month period ending June 30, 2018 to total $            per common share. In general, distributions on the common shares will be treated as distributions on corporate stock for federal income tax purposes. No Schedule K-1s will be issued with respect to the common shares, but instead holders of common shares will receive a Form 1099 with respect to distributions received on the common shares. Please read "—The Offering—Material U.S. Federal Income Tax Consequences."


The Appalachian Basin

        The Appalachian Basin, the area in which Antero Midstream and Antero Resources are exclusively based, covers a broad area with current industry activity extending primarily through West Virginia, Ohio and Pennsylvania in the Marcellus and Utica Shales. This area is considered a highly attractive natural resource producing region with a long history of natural gas, NGL and oil production. Importantly, the Appalachian Basin is strategically located near the high energy demand markets in the northeast and midwest regions of the United States. According to Baker Hughes, over 50% of the horizontal drilling rigs targeting shale gas reservoirs in the United States were operating in Appalachia as of December 31, 2016. Since January 2010, the combined natural gas production in the Marcellus and Utica Shales has increased by over 18 Bcf/d to 22 Bcf/d in 2016, representing over 30% of total U.S. natural gas production. According to Wood Mackenzie, Marcellus and Utica Shale production is expected to grow to 37 Bcf/d by 2021, which would account for 40% of overall expected natural gas production in the U.S.

Marcellus Shale

        The Devonian-aged Marcellus Shale is an unconventional reservoir that produces natural gas, NGL and oil and is the largest and most prolific unconventional natural gas reservoir in the U.S., producing nearly 25% of total U.S. natural gas supply in 2016. Antero Resources believes that the Marcellus Shale is a premier North American shale play due to its consistent and predictable geology, high well recoveries relative to drilling and completion costs and significant hydrocarbon resources in place, which collectively provide for attractive well economics. Antero Resources and other Marcellus Shale operators have continued to improve drilling and completion efficiencies by employing techniques such as multiple wells per pad, longer laterals, rotary steerable drilling, increasing concentrations of proppant and water and more efficient completion stage sequencing ("zipper fracs"), significantly increasing the level of economic inventory at current prices.

        According to Wood Mackenzie, natural gas production in the Marcellus Shale grew by more than 1.3 Bcf/d in 2016 (approximately 8%) and is expected to grow further from 18.6 Bcf/d in 2017 to more than 29.3 Bcfe/d in 2021, representing a 58% increase. We believe that Antero Resources' and Antero Midstream's assets located in the southwestern core of the Marcellus Shale are among the most productive and economic areas of the play, distinguished by processed EURs above 2.0 Bcfe per 1,000-feet of lateral length (assuming ethane rejection) and low finding and development costs.

Utica Shale

        The Ordovician-aged Utica Shale is an unconventional reservoir with productive limits covering a broad area primarily in West Virginia, Ohio and Pennsylvania. The richest and thickest concentration of organic-carbon content is present within the Point Pleasant Shale layer of the Lower Utica formation, which is Antero Resources' primary target in the Ohio Utica Shale. As is the case in the Marcellus Shale, Antero Resources and other Utica Shale producers have enjoyed improved drilling and completion efficiencies, resulting in an increased inventory of economic well locations and attractive well economics.

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        According to Wood Mackenzie, production in the Utica Shale grew by more than 1.2 Bcf/d in 2016 (approximately 45%) and is expected to grow further from 4.6 Bcf/d in 2017 to more than 7.7 Bcf/d in 2021, representing a 67% increase. We believe Antero Resources' and Antero Midstream's assets in the core of this play are located in the most productive and economic areas in the liquids-rich window, distinguished by industry-leading processed EURs ranging between 2.2 and 2.5 Bcfe per 1,000-feet of lateral length (assuming ethane rejection) and low finding and development costs. Additionally, the industry has drilled exploration wells in the deep dry gas window of the Utica Shale play in northeastern West Virginia and Pennsylvania. Results in this play have been encouraging with EURs ranging between 1.5 and 3.0 Bcf per 1,000-feet of lateral but with higher well costs than the Ohio Utica.

Antero Resources Corporation

        Antero Resources is Antero Midstream's largest customer and is the second largest natural gas and the largest NGL producer in Appalachia and the eighth largest natural gas producer in North America. Antero Resources' projected net daily production of 2.2 Bcfe/d (assuming the midpoint of Antero Resources' guidance for 2017) represents an 85% CAGR since 2010.

        The chart below illustrates the significant Appalachian Basin production growth achieved by Antero Resources since 2010. Antero Resources relies primarily on Antero Midstream to deliver the gathering, compression, processing and water handling and treatment infrastructure necessary to support its continued growth, which should result in significant increases in gathering, compression, processing, fresh water delivery and other fluid handling services volumes. Antero Resources has publicly announced annual production growth guidance of 20% to 25% for 2017 as compared to 2016 guidance of 1.8 Bcfe/d.

GRAPHIC


(1)
Based on Antero Resources' publicly disclosed forecast of estimated net daily production for 2017. We cannot assure you that actual net daily production will meet or exceed estimated amounts. For a description of certain factors that could negatively impact Antero Resources' business and cause its actual net daily production to be less than estimated amounts, please read "Risk Factors—Risks Related to Antero Midstream's Business—Because substantially all of Antero Midstream's revenue is derived from Antero Resources and Antero Resources' capital decisions drive our operations, any development that materially and adversely affects Antero Resources' operations, financial condition or market reputation could have a material and adverse impact on us."

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        The following table highlights the scale of Antero Resources' gross acreage position and gross drilling locations dedicated to Antero Midstream and to third parties for gathering and compression services and water services, respectively, as of December 31, 2016. With 3,630 identified potential horizontal well locations in Antero Resources' net 3P reserves as of December 31, 2016, Antero Resources maintains an approximate 21-year drilling inventory (based on its expected 2017 completion activity), which we believe will provide significant demand for further gathering and compression services and water services. In connection with its entry into the Joint Venture, Antero Midstream released to the Joint Venture its right to provide certain processing and fractionation services on 195,000 gross acres held by Antero Resources in Ritchie, Tyler and Wetzel Counties in West Virginia.

 
   
  Gross Drilling Locations(1)    
 
 
  Gross
Acres
  Dry
Gas
  Rich
Gas
  Highly
Rich
Gas
  Highly
Rich Gas/
Condensate
  Condensate   Total   2017
Estimated
Well Count
 

Marcellus

    530,000     572     543     1,125     683         2,923     135  

Utica

    172,000     253     105     41     130     178     707     35  

Total Acreage Dedicated to Antero Midstream for Water Services(2)

    702,000     825     648     1,166     813     178     3,630     170  

Total Acreage Dedicated to Third Parties for Gathering and Compression Services

    173,000     355     254                 609     N/A  

Total Acreage Dedicated to Antero Midstream for Gathering and Compression Services

    529,000     470     394     1,166     813     178     3,021     N/A  

(1)
Gross acres and gross undrilled proved, probable and possible locations as of December 31, 2016.

(2)
Antero Resources' estimated net proved, probable and possible reserves associated with this acreage were 15.4 Tcfe, 29.1 Tcfe and 1.9 Tcfe, respectively, as of December 31, 2016.


Antero Midstream Partners LP

        Antero Midstream is a growth-oriented master limited partnership 59% owned by Antero Resources and formed to own, operate and develop midstream energy infrastructure primarily to service Antero Resources' rapidly increasing production and completion activity under long-term, fixed-fee contracts. Antero Midstream's assets are located both in the southwestern core of the Marcellus Shale in northwest West Virginia and in the core of the Utica Shale in southern Ohio, which Antero Resources believes are two of the premier North American shale plays and are its primary operating areas.

Gathering and Processing Assets

        Antero Midstream's gathering assets consist of 8-, 12-, 16-, 20- and 24-inch low and high pressure gathering pipelines and compressor stations that collect natural gas and condensate from Antero Resources' wells in the Marcellus Shale in West Virginia and the Utica Shale in Ohio. Additionally, Antero Midstream owns a 15% non-controlling equity interest in Stonewall Gas Gathering, LLC, for which Antero Resources is an anchor shipper. As of December 31, 2016, Antero Midstream owned and operated 173 miles of low-pressure pipeline, 134 miles of high-pressure pipeline and 19 miles of condensate pipeline, as well as 11 compression stations with 1,135 MMcf/d of throughput capacity. Average daily low pressure gathering volumes increased from 1,016 MMcf/d for the year ended December 31, 2015 to 1,403 MMcf/d for the year ended December 31, 2016 as Antero Resources continued to increase its production. Under its gathering and compression agreement with Antero Resources, Antero Midstream receives a low pressure gathering fee of $0.31 per Mcf, a high pressure gathering fee of $0.19 per Mcf, a compression fee of $0.19 per Mcf and a condensate gathering fee of $4.17 per Bbl as of December 31, 2016. In each case, these fees are fixed and subject to annual CPI-based adjustments.

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        Antero Midstream's processing assets include a 50% non-operated equity interest in the Sherwood 7 natural gas processing plant in West Virginia through the Joint Venture. The Joint Venture also owns a 331/3% interest in the recently commissioned Hopedale 3 fractionator at the Hopedale complex. Please read "—Recent Developments—Antero Midstream Strategic Processing and Fractionation Joint Venture and Increased 2017 Guidance." In connection with its entry into the Joint Venture, Antero Midstream released to the Joint Venture its right to provide certain processing and fractionation services on 195,000 gross acres held by Antero Resources in Ritchie, Tyler and Wetzel Counties in West Virginia. The Joint Venture's processing activity commenced with Plant 7 at the Sherwood processing facility in the first quarter of 2017 and will continue with Plants 8, 9 and 10, which are under construction or planned and scheduled to be placed into service during the third quarter of 2017, first quarter of 2018 and third quarter of 2018, respectively.

        The Joint Venture's processing assets are underpinned by long-term, fee-based arrangements pursuant to which the Joint Venture will process Antero Resources' liquids-rich production from the Marcellus Shale. In addition to the processing assets, the Joint Venture will own C3+ fractionation capacity at the Hopedale complex in Harrison County, Ohio supported by Antero Resources and other third-party producers. The Joint Venture will have the option to participate in additional fractionation capacity in the future, contingent on further C3+ NGL production growth from the Joint Venture processing plants.

Water Handling and Treatment Assets

        Antero Midstream's water handling and treatment assets include fresh water delivery systems and other fluid handling assets. Antero Midstream's fresh water delivery assets consist of two independent systems that deliver fresh water from sources including the Ohio River, local reservoirs as well as several regional waterways. The other fluid handling assets also consist of flowback and produced water assets used to provide services for well completion and production operations in Antero Resources' operating areas. The fresh water delivery assets consist of permanent buried pipelines, surface pipelines and fresh water storage facilities, as well as pumping stations and impoundments to transport fresh water throughout the systems. The other fluid handling services assets consist of wastewater transportation, disposal and treatment, including services to be provided through the Antero Clearwater Facility, a 60,000 Bbl/d advanced wastewater treatment complex that is currently under construction in Doddridge County, West Virginia and is expected to be placed in service in the fourth quarter of 2017. Once in service, we expect the Antero Clearwater Facility will be the largest advanced wastewater treatment facility in the world specifically built for oil and gas operations. In West Virginia, Antero Midstream owned and operated 203 miles of buried and surface fresh water pipelines that service Antero Resources' drilling activities, as well as 22 centralized water storage facilities, as of December 31, 2016. In Ohio, Antero Midstream owned and operated 83 miles of buried and surface fresh water pipelines that service Antero Resources' drilling activities in the Utica Shale, as well as 14 centralized water storage facilities, as of December 31, 2016. Under its water services agreement with Antero Resources, Antero Midstream receives a fixed fee of $3.69 per barrel in West Virginia and a fixed fee of $3.64 per barrel in Ohio and all other locations for fresh water deliveries by pipeline directly to the well site as of December 31, 2016. In each case, these fees are fixed and subject to annual CPI-based adjustments.

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        The following table sets forth selected Antero Midstream operating and financial data for the years ended December 31, 2015 and 2016:

 
  Year Ended
December 31,
2015
  Year Ended
December 31,
2016
  Change  

Operating Data:

                   

Gathering—low pressure (MMcf/d)

    1,016     1,403     38 %

Gathering—high pressure (MMcf/d)

    1,186     1,316     11 %

Compression (MMcf/d)

    432     741     72 %

Fresh water delivery (MBbl/d)

    96     123     29 %

Financial Data:

   
 
   
 
   
 
 

Adjusted EBITDA ($MM)

  $ 280   $ 404     45 %

Distributable Cash Flow ($MM)

  $ 192   $ 353     84 %

Distributions ($MM)

  $ 132   $ 200     52 %

Distribution Coverage Ratio

    1.45x     1.76x     21 %


Recent Developments

Antero Midstream Strategic Processing and Fractionation Joint Venture and Increased 2017 Guidance

        On February 6, 2017, Antero Midstream announced the formation of a joint venture to develop processing and fractionation assets in Appalachia with MarkWest, a wholly owned subsidiary of MPLX. In connection with its entry into the Joint Venture, Antero Midstream released to the Joint Venture its right to provide certain processing and fractionation services on 195,000 gross acres held by Antero Resources in Ritchie, Tyler and Wetzel Counties in West Virginia. The Joint Venture will not participate in the six existing Sherwood plants, which will continue to be owned and operated solely by MarkWest. The existing plants have the capacity to process over 1.2 Bcf per day of liquids-rich gas and are currently running at full capacity. The Joint Venture processing facilities, starting with Plant 7, will be operated by MarkWest and will have the potential to support an incremental eleven plants, or 2.2 Bcf per day of capacity, to facilitate liquids-rich production growth from Antero Resources. In addition to the processing assets, the Joint Venture will own C3+ fractionation capacity at the Hopedale complex in Harrison County, Ohio supported by Antero Resources and other third-party producers.

        In connection with its entry into the Joint Venture, Antero Midstream increased its 2017 forecast for net income to $305 million to $345 million, Adjusted EBITDA to $520 million to $560 million and distributable cash flow ("DCF") to $405 million to $445 million, as a result of additional cash flows expected from the Joint Venture. Additionally, Antero Midstream reaffirmed its projected distribution growth of 28% to 30%, resulting in an average DCF coverage ratio of 1.30x to 1.45x on an annual basis. Additionally, Antero Midstream increased its 2017 capital budget to $800 million in connection with its entry into the Joint Venture.

Fourth Quarter 2016 Distribution Announcement for Antero Midstream

        On January 11, 2017, the board of directors of Antero Midstream's general partner declared a cash distribution of $0.28 per unit ($1.12 per unit annualized) for the fourth quarter of 2016. This distribution represents a 27% increase compared to the fourth quarter of 2015 and a 6% increase over the distribution paid with respect to the third quarter of 2016. This distribution is Antero Midstream's eighth consecutive quarterly distribution increase since the Antero Midstream IPO in November 2014. The distribution was paid on February 8, 2017 to Antero Midstream unitholders of record as of February 1, 2017. On February 9, 2017, in connection with this distribution, Antero Midstream's subordination period expired and all of the subordinated units in Antero Midstream converted to common units on a one-for-one basis. In connection with this distribution, approximately $             million was distributed to us on the IDRs with

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respect to the fourth quarter of 2016. Any additional distributions received by IDR LLC from Antero Midstream relating to periods prior to the closing of this offering will be distributed to the ARI Members.

2017 Guidance for Antero Resources and Antero Midstream

        On January 4, 2017, Antero Resources announced a 2017 drilling and completion capital budget of $1.3 billion and net production growth guidance of 20% to 25% for 2017 as compared to 2016 guidance of 1.8 Bcfe/d. In conjunction with Antero Resources' drilling and completion budget and production growth guidance, Antero Midstream announced a midstream capital budget of $525 million and distribution growth guidance of 28% to 30% for 2017 as compared to the prior year. The Antero Midstream capital budget was subsequently increased to $800 million upon announcement of the Joint Venture on February 6, 2017. Additionally, Antero Midstream expects a distribution coverage ratio of 1.30x to 1.45x over the corresponding period.


Antero Midstream's Business Strategies

        Antero Midstream's principal business objective is to increase the quarterly cash distributions that it pays to its unitholders over time while ensuring the ongoing stability of its business. Antero Midstream expects to achieve this objective through the following business strategies:

    Leveraging extensive asset base to meet Antero Resources' current and future infrastructure needs.  Antero Midstream owns and operates a newly-constructed, high-capacity asset base that will allow it to gather, compress and process significant incremental natural gas volumes, as well as fractionate incremental C3+ NGL volumes. Additionally, the high-capacity asset base will allow it to deliver incremental fresh water volumes and provide fluid-handling services for significant incremental produced and flowback water volumes. Antero Midstream intends to continue to develop its midstream infrastructure to move Antero Resources' growing production to market. Antero Resources' publicly announced production growth guidance of 20% to 25% in 2017 is expected to result in Antero Midstream throughput volume growth in excess of 20% to 25%, and is driven by Antero Resources' plan to complete approximately 170 horizontal wells with an average lateral length of approximately 9,300 feet, the vast majority of which are focused on Antero Midstream dedicated acreage. Antero Resources expects to execute advanced completions on these locations, resulting in increased water volumes and higher sand concentrations. In 2016, Antero Resources' advanced completions resulted in increased fresh water volumes delivered by Antero Midstream and improved throughput on the gathering and compression assets driven by higher overall wellhead recoveries. In addition, as of December 31, 2016, Antero Resources' drilling inventory consisted of 3,630 identified proved, probable and possible horizontal well locations on its contiguous acreage position, giving Antero Resources an approximate 21-year drilling inventory (based on expected 2017 completion activity) and, consequently, visible long-term demand for Antero Midstream's services.

    Focusing on stable, fixed-fee business to avoid direct commodity price exposure.  Antero Midstream's gathering, compression, processing, fractionation and water services arrangements with Antero Resources provide for a fixed-fee structure, and Antero Midstream intends to continue to pursue additional fixed-fee opportunities with Antero Resources and third parties in order to avoid direct commodity price exposure. Antero Midstream will focus on obtaining additional long-term commitments from customers, which may include reservation-based charges, volume commitments and acreage dedications.

    Investing in a significant backlog of attractive organic growth opportunities.  Antero Midstream's strategy is to organically develop midstream infrastructure to support Antero Resources' robust development program. Antero Midstream believes that organic projects will be a key driver of its growth in the future and expects to construct additional gathering systems, compressor stations, processing and fractionation plants and water handling and treatment assets to meet Antero

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      Resources' significant long-term production growth expectations. We believe Antero Midstream's organic growth strategy generally provides more attractive returns and project economics than an approach based on third-party acquisitions or sponsor drop-downs, as it avoids the risks and costs associated with the competitive acquisition market and the reliance on capital markets for acquisition financing. Additionally, Antero Midstream's significant acreage dedication and relationship with Antero Resources provides Antero Midstream with increased visibility into the timing and magnitude of Antero Resources' development program, supporting a just-in-time approach to infrastructure investment and further enhancing project economics.

    Growing Antero Midstream's business through Antero Resources' continuing expansion of its acreage footprint in the Marcellus and Utica Shales.  Antero Resources' management team has significant experience in mergers and acquisitions and will selectively review opportunities to acquire assets from third parties. From its initial public offering in 2013 through 2016, Antero Resources has increased its overall acreage position by 45%, driving incremental greenfield expansion projects.

    Expanding beyond existing services to operate across the midstream value chain.  While traditionally Antero Midstream has provided gathering, compression and water services to Antero Resources, Antero Midstream has recently expanded its midstream services to include natural gas processing and C3+ NGL fractionation through its interest in the Joint Venture. In addition, Antero Midstream may expand its existing services to include other midstream services such as long-haul interstate pipelines, NGL product pipelines, terminaling and storage to be provided to Antero Resources and other third parties. Antero Midstream expects significant growth in demand for all of its midstream services as a result of the anticipated production growth from Antero Resources and third parties based on the increasing productivity of completed wells and low cost nature of the Marcellus and Utica Shales.

    Expanding Antero Midstream's business by developing, over the long term, a third-party customer base in the most productive natural gas basins in North America.  Antero Resources represented 99.86% of Antero Midstream's revenues for the year ended December 31, 2016, while third-party customers represented the remaining amount. While Antero Midstream will devote substantially all of its resources in the near term to meeting Antero Resources' needs, Antero Midstream expects to market its services to, and pursue customer relationships with, third-party producers over the longer term in the highly productive, low cost Marcellus and Utica Shales. We believe that Antero Midstream's significant footprint of gathering, compression, water handling and water treatment infrastructure in the Marcellus and Utica Shales provides it with a competitive advantage that we believe will allow Antero Midstream to attract third-party throughput volumes in the future. However, Antero Midstream's forecast contains no third-party volumes for the twelve-month period ending June 30, 2018.

        Antero Midstream cannot assure you, however, that it will be able to execute its business strategies described above. For further discussion of the risks that Antero Midstream faces, please read "Risk Factors—Risks Related to Antero Midstream's Business."


Antero Midstream's Competitive Strengths

        Antero Midstream is well-positioned to significantly grow distributions on its partnership interests, including its IDRs, by capitalizing on the following competitive strengths:

    Sustainable outsized growth.  Antero Midstream commenced cash distributions on its IDRs in the third quarter of 2015. In addition, Antero Midstream's fourth quarter 2016 distribution of $0.28 per unit represented a 65% increase as compared to its minimum quarterly distribution of $0.17 per unit and represented the second quarter that Antero Midstream's distribution was above the 50% tier distribution target amount, entitling the IDRs to receive up to 50% of all incremental cash distributed in a given quarter after each common and subordinated unit of Antero Midstream

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      received $0.255 per unit for that quarter. Since its initial public offering in November 2014, Antero Midstream has increased its quarterly distribution each quarter while maintaining average distributable cash flow coverage of 1.58x. Antero Midstream expects to declare distributions in 2017 that are 28% to 30% above the distributions declared for 2016.

    Appalachia core focused with exposure to diverse hydrocarbon mix.  Antero Midstream believes it has the largest dedicated acreage position in the core of the combined Marcellus and Utica Shales due to its gathering, compression, processing, fractionation and water services arrangements with Antero Resources, providing a diverse investment opportunity set for gas, NGL and condensate gathering, compression, processing and fractionation, as well as water handling and treatment projects. The diverse hydrocarbon mix provides Antero Midstream with multiple points at which to service a hydrocarbon unit generating multiple investment and growth opportunities over time. The anticipated natural gas, NGL, condensate and fresh and produced and flowback water volume growth is driven by Antero Resources' peer-leading development program in two of the lowest-cost shale plays in North America.

    Economic strength of Antero Resources' development program.  We believe the attractiveness of Antero Resources' portfolio of both liquids-rich and dry acreage and its low development cost per unit will support long-term demand for Antero Midstream's services in a variety of commodity price environments. The economic strength of Antero Resources' development program is substantially supported by:

    Antero Resources' multi-decade drilling inventory.    Antero Resources' drilling inventory as of December 31, 2016 consisted of 3,630 identified potential horizontal well locations, which include more than 2,500 locations that deliver breakeven economics (defined as a pre-tax rate of return of 20% at below $3.00 per MMBtu NYMEX prices assuming December 31, 2016 strip pricing for oil and NGLs). Antero Resources believes its core inventory is the largest in Appalachia, with 3,400 of such identified locations being in the core of the Marcellus and Utica Shales as of December 31, 2016. Based on its expected 2017 completion activity, these core locations give Antero Resources a 20-year drilling inventory as of December 31, 2016.

    Antero Resources' exposure to a large resource of liquids-rich gas and condensate.    Liquids-rich gas production generally enhances well economics due to the processing margin generated by typically higher-value NGL products, such as propane and butane. In addition, the wellhead condensate often associated with liquids-rich production can further increase well economics. Approximately 70% of Antero Resources' 3,630 identified potential horizontal well locations as of December 31, 2016 target the liquids-rich gas regions of the Marcellus and Utica Shales.

    Antero Resources' status as a low-cost leader.    Antero Resources has implemented operational efficiencies to give it some of the lowest development costs per Mcfe in the Marcellus and Utica Shales, such as (i) pad drilling that is expected to average nine wells per pad in the Marcellus Shale and six wells per pad in the Utica Shale in 2017, (ii) drilling longer laterals expected to average 9,300 feet in 2017, (iii) the use of rotary steerable drilling equipment and increased mud pump circulation rates, (iv) the use of shorter stage lengths and advanced completions incorporating increased proppant and fluid loading, (v) the use of Antero Midstream's fresh water delivery systems, (vi) more efficient completion stage sequencing, or zipper fracs and (vii) the use of less expensive, intermediate drilling rigs to drill to the kick-off point just above the target formation, prior to the arrival of large drilling rigs to drill the horizontal wellbore.

    Antero Resources' access to committed processing and firm takeaway capacity in the Marcellus and Utica Shales.    Antero Resources' existing contractual commitments for processing and firm long-haul transportation help minimize disruptions to its drilling program that might otherwise exist as a result of insufficient outlets for growing production as well as optimize pricing for its

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        products. Antero Resources has committed to a total of 2.0 Bcf/d of processing capacity in the Marcellus Shale, 1.2 Bcf/d of which is currently in service. Similarly, Antero Resources has 600 MMcf/d of contracted processing capacity in the Utica Shale, all of which is currently in service. In addition, Antero Resources has secured an average of 4.85 Bcf/d of long-haul natural gas firm transportation capacity or firm sales that is expected to be in service by year end of 2018. Antero Resources has also committed to 20,000 Bbl/d of ethane takeaway capacity to Mont Belvieu and has entered into an agreement to provide an additional 30,000 Bbl/d of ethane to the planned Shell Chemical LP ("Shell") ethane cracker. Additionally, Antero Resources has entered into firm transportation agreements on Mariner East 2 for 61,500 Bbl/d of capacity, consisting of 11,500 Bbl/d of ethane, 35,000 Bbl/d of propane and 15,000 Bbl/d of butane and has doubling rights on its propane and butane commitments that would result in capacity of 70,000 Bbl/d and 30,000 Bbl/d, respectively. Antero Midstream believes its midstream infrastructure, together with Antero Resources' significant processing and takeaway capacity, will allow Antero Resources to commercialize its production more quickly at favorable prices and keep pace with its robust drilling plan.

      Antero Resources' peer-leading hedging program.    Antero Resources maintains a hedging program designed to mitigate volatility in commodity prices and regional basis differentials and to protect its expected future cash flows. As of December 31, 2016, Antero Resources had entered into hedging contracts through December 31, 2022 covering a total of approximately 3.4 Tcfe of its projected natural gas, NGLs and oil production at a weighted average index equivalent price of $3.63 per MMBtu. Pursuant to this hedging program, Antero Resources has hedged volumes of 2,163 BBtu/d, 2,015 BBtu/d and 2,330 BBtu/d at weighted average prices of $3.51 MMBtu, $3.91 MMBtu and $3.70 MMBtu for 2017, 2018 and 2019, respectively. We believe that Antero Resources' active hedging program will allow its drilling schedule to remain robust through a variety of commodity price environments.

    Extensive dedication, system scale and long-term, fixed fee contracts to support stable cash flows.  As of December 31, 2016, Antero Resources has dedicated all of its 702,000 gross acres (616,000 net acres) to Antero Midstream for gathering and compression services, except for approximately 173,000 gross acres subject to third-party commitments, and substantially all of Antero Resources' approximate 702,000 gross acres to Antero Midstream for water services. In addition, the gathering and compression agreement provides that any acreage that Antero Resources acquires in West Virginia, Ohio and Pennsylvania subsequent to the Antero Midstream IPO completed in November 2014 that is not subject to a pre-existing dedication or other third-party commitment, will be dedicated to Antero Midstream for gathering and compression services and, with respect to certain acreage in Ohio and West Virginia, Antero Midstream's integrated water services pursuant to the water services agreement. We believe that Antero Resources' drilling activity will result in the significant growth of Antero Midstream's operations. Antero Midstream's fixed-fee, long-term contract structure helps to eliminate direct exposure to commodity price risk and provide Antero Midstream with more stable long-term cash flow.

    Financial flexibility and strong capital structure.  As of December 31, 2016 and after giving effect to Antero Midstream's offering of 6.9 million common units on February 6, 2017 and the Joint Venture, Antero Midstream had approximately $1.2 billion of available borrowing capacity under its $1.5 billion revolving credit facility, as well as approximately $185 million of available capacity under its at-the-market equity offering program. We believe that Antero Midstream's borrowing capacity, the available offering capacity under its at-the-market equity offering program and the organic nature of its business plan, which significantly limits the need for access to the debt and equity capital markets, provides Antero Midstream with the financial flexibility necessary to execute its business strategy.

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    Experienced and incentivized management team led by co-founders.  Antero Resources' Chairman and Chief Executive Officer and its President and Chief Financial Officer are co-founders of Antero Resources and its officers, who also manage Antero Midstream's business and will manage our business, have an average of over 30 years of industry experience and have successfully built, grown and sold two unconventional resource-focused upstream companies and one midstream company in the past 15 years. We believe Antero Resources' experience and expertise from both an upstream and midstream perspective provides a distinct competitive advantage. Through Antero Resources' ownership of 59% of the common units of Antero Midstream, the management team of Antero Resources and Antero Midstream is highly incentivized to grow Antero Midstream's distributions and the value of its business.

        We cannot assure you, however, that Antero Midstream will be able to utilize its competitive strengths to successfully execute its business strategies described above. For further discussion of the risks and challenges that Antero Midstream faces, please read "Risk Factors—Risks Related to Antero Midstream's Business."


Organizational Structure

        The diagram below depicts our organizational structure immediately following the closing of this offering (assuming the underwriters' option to purchase additional common shares is not exercised):

GRAPHIC


(1)
Series B Units represent the right to receive up to 6% of the aggregate distributions paid by IDR LLC in excess of $7.5 million. Each Series B Holder will also have the right to redeem all or a portion of its vested Series B Units in exchange for newly-issued common shares in us with a value equal to its pro rata share of up to 6% of any increase in our equity value (calculated by

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    reference to the 20-day volume weighted average price of our common shares preceding the date of the redemption request) in excess of $2.0 billion.

(2)
We own all of the capital interests in IDR LLC, which owns all of the IDRs in Antero Midstream. Following the completion of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on its IDRs.

Reorganization

        Our Predecessor was formed as a limited liability company in September 2013 and has elected to be taxed as a corporation for U.S. federal income tax purposes. In connection with the completion of this offering, certain reorganization transactions will be effected, which will result in the revised organizational structure depicted above. For additional information regarding the Reorganization, please read "Organizational Structure—Reorganization."

        In connection with the Reorganization, we will convert into a Delaware limited partnership and will elect to be taxed as a corporation for U.S. federal income tax purposes. Our sole assets consist of our interest in the general partner of Antero Midstream and all of the capital interests in IDR LLC, which directly owns the IDRs.

Series B Units and Redemption Right

        IDR LLC has two classes of membership interests: (i) capital interests referred to as Series A Units and (ii) profits interests referred to as Series B Units. Following the completion of this offering, we will continue to own all of the Series A Units and the Series B Holders will continue to own all of the Series B Units.

        The Series B Holders will receive an aggregate distribution of up to 6% of all quarterly cash distributions in excess of $7.5 million distributed by Antero Midstream on the IDRs and we will receive all remaining distributions. The Series B Units are subject to restrictions on transfer and vest over three years in one-third increments upon each anniversary of the vesting commencement date.

        Each Series B Holder will also have the right to redeem all or a portion of its vested Series B Units in exchange for newly-issued common shares in us with a value equal to its pro rata share of up to 6% of any increase in our equity value (calculated by reference to the 20-day volume weighted average price of our common shares preceding the date of the redemption request) in excess of $2.0 billion. We refer to this right as the Redemption Right. In no event will the aggregate number of newly-issued common shares issued pursuant to the Redemption Right exceed 6% of the total number of our issued and outstanding common shares. Upon the exercise of the Redemption Right, the redeeming member will surrender its Series B Units to IDR LLC for cancellation.

        For additional information, please read "Certain Relationships and Related Party Transactions—Limited Liability Company Agreement of IDR LLC."

Management

        AMGP GP LLC, our general partner ("AMGP GP"), will manage our operations and activities, including, among other things, establishing the quarterly cash distribution for our common shares and cash reserves it believes are prudent to provide for the proper conduct of our business. Antero Midstream Partners GP LLC ("AMP GP"), the general partner of Antero Midstream, will be responsible for the management of Antero Midstream's operations and activities, which are designed to service Antero Resources as the primary beneficiary of Antero Midstream. However, as the managing member of AMP GP, we will appoint all of the members of the board of directors of AMP GP. In addition, we are the sole managing member of IDR LLC. As a result, we will be responsible for the business and affairs of Antero Midstream and IDR LLC, and our general partner will be responsible for exercising on our behalf any rights we have with respect to AMP GP and IDR LLC.

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        Our general partner's limited liability company agreement will provide for a board of directors consisting of up to          members. Following the Reorganization, the Sponsors will collectively own 100% of the membership interest in our general partner and will have the ability to appoint all the members of our general partner's board of directors, including at least three directors that are independent and qualify for service on the audit committee in accordance with applicable NYSE and SEC rules. The limited liability company agreement of our general partner will further provide that the Chief Executive Officer of our general partner will serve as a director and chairman of the board of directors of our general partner.

        For additional information regarding our governance and related matters, please read "Management—Designation of Directors."

Services Agreement

        In connection with the closing of this offering, we, our general partner, IDR LLC and Antero Resources will enter into a services agreement that will govern, among other things, certain administrative services that Antero Resources will provide to us.

        We and our general partner have no employees. All of our officers and other personnel necessary for our business to function (to the extent not outsourced) will be employed by Antero Resources, and our general partner will pay Antero Resources an annual fee for corporate, general and administrative services. This fee will initially be $             million per year and will be subject to an annual CPI-based adjustment, beginning on January 1, 2018. The fee will also be subject to adjustment to reflect any increase in the cost of providing services due to changes in applicable law, rules or regulations and any increase in the scope and extent of the services provided. The fee will not be decreased below the initial fee unless the type or extent of services provided materially decreases. In addition to the general and administrative services provided to us by Antero Resources, we also expect to incur direct annual expenses of approximately $       million per year for recurring costs associated with being a separate publicly traded entity, including expenses associated with (i) compensation for new directors, (ii) incremental director and officer liability insurance, (iii) listing on the NYSE, (iv) investor relations, (v) legal services, (vi) tax services and (vii) accounting services. We will be responsible for all of these direct expenses and income taxes payable by us.

        In addition to the fee and expenses described above, we will reimburse Antero Resources for costs and expenses to the extent that such costs and expenses are directly allocable to the provision of services to us, our general partner, or our subsidiaries (other than Antero Midstream and its subsidiaries), including expenses associated with insurance coverage, recurring costs associated with being a separate publicly traded entity, and taxes, other than payroll taxes, or other direct operating expenses, paid by Antero Resources for our benefit. We will also reimburse our general partner for any additional expenses incurred on our behalf or to maintain our legal existence and good standing. There is no limit on the amount of fees and expenses our general partner may be required to pay to its affiliates on our behalf pursuant to the services agreement. Please read "Certain Relationships and Related Party Transactions" for additional information.


Principal Executive Offices

        Our principal executive offices are located at 1615 Wynkoop Street, Denver, Colorado 80202, and our telephone number is (303) 357-7310. Our website is located at www.                .com. We expect to make available our periodic reports and other information filed with or furnished to the SEC free of charge through our website, as soon as reasonably practicable after those reports and other information are electronically filed with or furnished to the SEC. Information on our website or any other website is not incorporated by reference herein and does not constitute a part of this prospectus.

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Risk Factors

        An investment in our common shares involves risks associated with our business and our organizational structure. Because of our relationship with Antero Midstream, adverse developments or announcements concerning Antero Midstream could materially adversely affect our business. We have presented below a summary of certain key risk factors that you should consider in evaluating an investment in our common shares. However, this list is not exhaustive and you should read the full discussion of these risks and the other risks described in "Risk Factors." You should consider carefully these risk factors together with all of the other information included in this prospectus before you invest in our common shares.

Risks Inherent in an Investment in us

    Our cash flow will be entirely dependent upon the ability of Antero Midstream to make cash distributions on the IDRs.

    In the future, we may not have sufficient cash to pay our estimated initial quarterly distribution or to increase distributions.

    The assumptions underlying the estimated cash available for distribution that we included in "Our Cash Distribution Policy and Restrictions on Distributions" are inherently uncertain and are subject to significant business, financial, regulatory and competitive risks and uncertainties that could cause actual results to differ materially from those forecasted.

    Our right to receive distributions paid by Antero Midstream on the IDRs may be limited or modified by our general partner without the consent of our shareholders, which may reduce cash distributions to you.

    A reduction in Antero Midstream's distributions will disproportionately affect the amount of cash distributions on the IDRs.

Risks Related to Conflicts of Interest

    Conflicts of interest may arise as a result of our organizational structure and the relationships among us, Antero Midstream, our respective general partners, Antero Resources and other affiliated entities.

    Our partnership agreement defines our general partner's duties to us and contains provisions that reduce the remedies available to our shareholders for actions that might otherwise be challenged as breaches of fiduciary or other duties under state law.

    The Sponsors may have interests that conflict with holders of our common shares.

    Antero Resources does not own our general partner and is under no obligation to adopt a business strategy that favors us.

    Our general partner's affiliates and the Sponsors may compete with us.

Risks Related to Antero Midstream's Business

    Because substantially all of Antero Midstream's revenue is derived from Antero Resources and Antero Resources' capital decisions drive our operations, any development that materially and adversely affects Antero Resources' operations, financial condition or market reputation could have a material and adverse impact on us.

    The amount of cash Antero Midstream can distribute on its units principally depends upon the amount of cash Antero Midstream generates from its operations, which will fluctuate from quarter to quarter.

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    Because of the natural decline in production from existing wells, Antero Midstream's success depends, in part, on Antero Resources' ability to replace declining production and Antero Midstream's ability to secure new sources of natural gas from Antero Resources or third parties. Additionally, Antero Midstream's water services are directly associated with Antero Resources' well completion activities, the volumes of produced water from such activities and water needs, which are partially driven by horizontal lateral lengths and the number of completion stages per well. Any decrease in volumes of natural gas that Antero Resources produces or any decrease in the number of wells that Antero Resources completes could adversely affect Antero Midstream's business and operating results.

    The gathering and compression agreement only includes minimum volume commitments under certain circumstances.

    Antero Midstream may not be able to attract third-party gathering and compression volumes or opportunities to provide water services, which could limit its ability to grow and maintain its dependence on Antero Resources.

    Antero Midstream owns a 50% interest in the Joint Venture, which will be operated by MarkWest. While Antero Midstream has the ability to influence certain business decisions affecting the Joint Venture, the success of its investment in the Joint Venture will depend on MarkWest's operation of the Joint Venture.

    If the Joint Venture is not successful or if the Joint Venture does not perform as expected, Antero Midstream's future financial performance may be negatively impacted.

Tax Risks

    The tax treatment of Antero Midstream depends on its status as a partnership for U.S. federal income tax purposes, as well as it not being subject to a material amount of entity-level taxation by individual states. If the Internal Revenue Service were to treat Antero Midstream as a corporation or Antero Midstream becomes subject to additional amounts of entity-level taxation for state or foreign tax purposes, it would reduce the amount of cash available for distribution to us.

    The tax treatment of publicly traded partnerships such as Antero Midstream could be subject to potential legislative, judicial or administrative changes and differing interpretations, possibly on a retroactive basis.


Summary of Conflicts of Interest and Duties

        Our general partner has a duty to manage us in a manner it believes is in the best interests of our partnership and our shareholders. However, the officers and directors of our general partner also have a duty to manage the business of our general partner in a manner they believe is in the best interests of its owners, the Sponsors. As a result of this relationship, conflicts of interest may arise in the future between us and our shareholders, on the one hand, and our general partner and its affiliates, including the Sponsors, on the other hand. For example, our general partner will be entitled to make determinations that affect the amount of cash distributions we make to our shareholders. For a more detailed description of the conflicts of interest and duties of our general partner, please read "Risk Factors—Risks Related to Conflicts of Interest" and "Conflicts of Interest and Fiduciary Duties."

        We anticipate that all of the officers and a majority of the directors of our general partner will also be officers or directors of Antero Resources and Antero Midstream and, as a result, have separate duties that govern their management of the respective businesses of those entities. Consequently, these officers and directors may encounter situations in which their obligations to us, on the one hand, and Antero Resources or Antero Midstream, on the other hand, are in conflict. The resolution of these conflicts may not always be in our best interest or that of our shareholders.

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        In addition, our general partner's officers, who also serve as officers of Antero Resources or AMP GP, may face conflicts in allocating their time spent on our behalf, on behalf of Antero Resources and on behalf of Antero Midstream. These time allocations may adversely affect our, Antero Resources' or Antero Midstream's results of operations, cash flows and financial condition. It is unlikely that these allocations will be the result of arms-length negotiations between our general partner, Antero Resources and AMP GP.

        Delaware law provides that Delaware limited partnerships may, in their partnership agreements, expand, restrict or eliminate the fiduciary duties owed by the general partner to limited partners and the partnership. Pursuant to these provisions, our partnership agreement will contain various provisions that eliminate and replace the fiduciary duties that would otherwise be owed by our general partner with contractual standards governing the duties of our general partner and the methods of resolving conflicts of interest. The effect of these provisions is to restrict the remedies available to our shareholders for actions taken by our general partner that might otherwise constitute breaches of its fiduciary duties. Our partnership agreement will also provide that affiliates of our general partner, including the Sponsors and their respective affiliates, are not restricted from competing with us, and neither our general partner nor its affiliates have any obligation to present business opportunities to us. By purchasing a common share, the purchaser agrees to be bound by the terms of our partnership agreement, and each common shareholder is treated as having consented to various actions and potential conflicts of interest contemplated in our partnership agreement that might otherwise be considered a breach of fiduciary or other duties under Delaware law. Please read "Conflicts of Interest and Fiduciary Duties—Fiduciary Duties of Our General Partner" for a description of the fiduciary duties imposed on our general partner by Delaware law, the replacement of those duties with contractual standards under our partnership agreement and certain legal rights and remedies available to holders of our common shares. For a description of our other relationships with our affiliates, please read "Certain Relationships and Related Party Transactions."


Implications of Being an Emerging Growth Company

        We qualify as an "emerging growth company" as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. An emerging growth company may take advantage of specified reduced reporting and other regulatory requirements for up to five years that are otherwise applicable generally to public companies. These provisions include:

    a requirement to present only two years of audited financial statements and only two years of related Management's Discussion and Analysis;

    exemption from the auditor attestation requirement on the effectiveness of our system of internal control over financial reporting pursuant to Section 404 of the Sarbanes-Oxley Act;

    exemption from compliance with any new requirements adopted by the Public Company Accounting Oversight Board requiring mandatory audit firm rotation or a supplement to the auditor's report in which the auditor would be required to provide additional information about the audit and the financial statements of the issuer; and

    reduced disclosure about executive compensation arrangements in our periodic reports.

        In addition, the JOBS Act provides that an emerging growth company can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. However, we intend to irrevocably opt out of the extended transition period.

        Except as set forth in the immediately preceding paragraph, we have elected to take advantage of all other applicable JOBS Act provisions. Accordingly, the information that we provide you may be different than what you may receive from other public companies in which you hold equity interests.

        We will cease to be an emerging growth company prior to the last day of the fiscal year following the fifth anniversary of this offering if we (i) have more than $1.0 billion in annual revenues, (ii) issue more

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than $1.0 billion of non-convertible debt over a three-year period or (iii) qualify as a "large accelerated filer" under the SEC rules, which requires, among other things, that we have more than $700 million in market value of our limited partner interests held by non-affiliates on the last business day of the most recently completed second fiscal quarter and have been subject to the reporting requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 for at least 12 calendar months.

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The Offering

Common Shares Offered by the Selling Shareholder               common shares.

 

 

The selling shareholder may sell up to            additional common shares if the underwriters exercise in full their option to purchase additional common shares.

Common Shares Outstanding Before and After this Offering

 

            common shares.

Common Shares Held by the Selling Shareholder after the Offering

 

            common shares (or            common shares if the underwriters exercise in full their option to purchase additional common shares).

Use of Proceeds

 

We will not receive any proceeds from this offering. We expect the selling shareholder to receive net proceeds of approximately $            million, based upon the initial public offering price of $            per common share, after deducting underwriting discounts. Please read "Use of Proceeds" and "Principal and Selling Shareholders."

Cash Distributions

 

We expect our quarterly cash distributions for the twelve-month period ending June 30, 2018 to total $      per common share. Our ability to pay cash distributions at this rate is subject to various restrictions and other factors described in more detail under the heading "Our Cash Distribution Policy and Restrictions on Distributions."

 

 

All of our cash flow is derived from the IDRs, which entitle IDR LLC to receive increasing percentages (up to a maximum of 50%, to the extent not modified) of any cash distributed by Antero Midstream in excess of $0.1955 per Antero Midstream common unit per quarter, including 50% of all incremental cash distributed by Antero Midstream per quarter after Antero Midstream has distributed $0.2550 per unit in respect of its common units for that quarter. IDR LLC, in turn, makes cash distributions to us, as holders of the Series A Units, and to the holders of the Series B Units.

 

 

We will pay you a prorated cash distribution for the first quarter that we are publicly traded. This cash distribution will be paid for the period beginning on the closing date of this offering and ending on the last day of that fiscal quarter. We expect to pay this cash distribution in                2017.

 

 

Our pro forma estimated cash available for distribution for the years ended December 31, 2015 and 2016 would have been approximately $0 and $9 million, respectively.

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    We believe that we will have sufficient available cash to pay the full annualized quarterly distribution for the twelve-month period ending June 30, 2018. Please read "Our Cash Distribution Policy and Restrictions on Distributions."

Issuance of Additional Securities

 

We can issue an unlimited number of additional common shares and other equity interests without the consent of our shareholders. Please read "Description of Our Partnership Agreement—Issuance of Additional Securities."

Limited Voting Rights

 

Our general partner will manage and operate us. You will have only limited voting rights on matters affecting our business. Holders of our common shares vote as a single class on all matters presented to our shareholders for their vote or approval, except as otherwise required by applicable law or our partnership agreement.

 

 

Our shareholders will not have the ability to elect our general partner or vote in the election of the directors of our general partner. Our general partner may not be removed unless that removal is for cause and is approved by a vote of the holders of at least 80% of our outstanding common shares, including any common shares owned by our general partner, the Sponsors and their respective affiliates, voting together as a single class. Following the closing of this offering, the Sponsors will own a sufficient number of our common shares to prevent the removal of our general partner. Please read "Description of Our Partnership Agreement—Limited Voting Rights."

Limited Call Right

 

If at any time our general partner, the Sponsors (or certain transferees in private, non-exchange transactions) and their respective affiliates own more than 80% of our outstanding common shares (including common shares issued in connection with the redemption of Series B Units), our general partner will have the right, but not the obligation, to purchase all of the outstanding common shares, other than those owned by our general partner, the Sponsors and their respective affiliates, at a price not less than the then current market price of such common shares. At the closing of this offering, our general partner will not own any of our outstanding common shares and the Sponsors will own approximately            % of our outstanding common shares (            % if the underwriters exercise in full their option to purchase additional common shares from us).

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Redemption Right   Following the completion of this offering, each Series B Holder will have the right to redeem all or a portion of its vested Series B Units in exchange for newly-issued common shares in us with a value equal to its pro rata share of up to 6% of any increase in our equity value (calculated by reference to the 20-day volume weighted average price of our common shares preceding the date of the redemption request) in excess of $2.0 billion; provided that, at our election, we may effect a direct exchange of such common shares for such vested Series B Units. For additional information, please read "Certain Relationships and Related Party Transactions—Limited Liability Company Agreement of IDR LLC."

Material U.S. Federal Income Tax Consequences

 

Although we will be a limited partnership following the completion of the Reorganization, we will elect to be taxed as a corporation for U.S. federal income tax purposes. Under current law, our federal taxable income will be subject to a U.S. federal income tax at rates of up to 35% (and a 20% alternative minimum tax on our alternative minimum taxable income in certain cases), and we may be liable for state income taxes at varying rates in states in which Antero Midstream operates.

 

 

Distributions on the common shares will be treated as distributions on corporate stock for U.S. federal income tax purposes. No Schedule K-1s will be issued with respect to the common shares; instead holders of common shares will receive a Form 1099 with respect to distributions received on the common shares. Like distributions on corporate stock, our distributions will only be treated as dividends to the extent of our current or accumulated earnings and profits (as computed for U.S. federal income tax purposes). We generally expect that we will have current or accumulated earnings and profits, and, accordingly, expect the majority of our distributions to be treated as dividends for U.S. federal income tax purposes.

 

 

In addition, as Series B Holders cause IDR LLC to redeem, or at our election we cause such holders to directly exchange with us, Series B Units for our common shares in the future, we expect to benefit from additional tax deductions resulting from those redemptions or exchanges, as the case may be, the amount of which will vary depending on the value of the common shares at the time of the redemption or exchange. For additional information relating to our exchangeable structure, please read "Organizational Structure."

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Directed Share Program   At our request, the underwriters have reserved for sale, at the initial public offering price, up to    % of the common shares offered by this prospectus for sale to some of the directors, officers, employees, business associates and related persons of our general partner, Sponsors and their respective affiliates. If these persons purchase reserved common shares, the purchased common shares will be subject to the lock-up restrictions described in "Underwriting" and the purchased common shares reduce the number of common shares available for sale to the general public. Any reserved common shares that are not so purchased will be offered by the underwriters to the general public on the same terms as the other common shares offered by this prospectus. Please read "Underwriting."

Agreement to be Bound by the Partnership Agreement

 

By purchasing a common share, you will be deemed to have agreed to be bound by all the terms of our partnership agreement.

Risk Factors

 

For a discussion of factors you should consider before buying our common shares, see "Risk Factors."

Listing and Trading Symbol

 

We have applied to list our common shares on the New York Stock Exchange under the symbol "AMGP."

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Summary Historical Financial Data

        Prior to the formation of IDR LLC, our Predecessor, Antero Resources Midstream Management LLC, owned the general partner interest in Antero Midstream and the IDRs, and in connection with IDR LLC's formation, our Predecessor conveyed the IDRs to IDR LLC in exchange for all of the Series A Units. In connection with the Reorganization, our Predecessor will (i) convey its 100% interest in the non-economic general partner interest in Antero Midstream to AMP GP, a wholly owned subsidiary of our Predecessor and (ii) convert into a Delaware limited partnership named Antero Midstream GP LP, which will elect to be taxed as a corporation for U.S. federal income tax purposes.

        The historical financial data of our Predecessor reflect our ownership of the general partner interest in Antero Midstream through our interest in AMP GP and our ownership of the IDRs through our ownership of the capital interests of IDR LLC, which we will control as managing member. We have used the equity method to account for our investment in Antero Midstream because we are not the primary beneficiary of Antero Midstream for financial reporting purposes. Additionally, we currently have no separate operating activities apart from those conducted by Antero Midstream, and our cash flows will consist solely of distributions from IDR LLC related to its ownership of the IDRs.

        In the sections below, we present historical financial information for both our Predecessor and Antero Midstream.

Predecessor Summary Historical Financial Data

        The summary historical statements of operations and cash flow data of our Predecessor for the years ended December 31, 2015 and 2016 and the balance sheet data as of December 31, 2015 and 2016 are derived from the audited financial statements of our Predecessor included elsewhere in this prospectus.


Summary Historical Financial Table

 
  Year Ended
December 31,
 
 
  2015   2016  
 
  (in thousands, except
per share amounts)

 

Statement of Operations Data:

             

Equity in earnings of Antero Midstream Partners LP

  $ 1,264   $ 16,944  

Interest income

        1  

Total income

    1,264     16,945  

General and administrative expense

        815  

Income before income taxes

    1,264     16,130  

Provision for income taxes

    (483 )   (6,419 )

Net income and comprehensive income

  $ 781   $ 9,711  

Pro forma basic earnings per share

  $     $    

Pro forma diluted earnings per share

  $     $    

Balance Sheet Data (at period end):

             

Cash

  $ 72   $ 9,609  

Investment in Antero Midstream Partners LP

    969     7,543  

Total assets

    1,041     17,369  

Cash Flow Data:

             

Net cash provided by operating activities

  $ 295   $ 9,537  

Net cash used in financing activities

    (223 )    

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Antero Midstream Summary Historical Financial Data

        The summary historical statements of operations and cash flow data of Antero Midstream for the years ended December 31, 2015 and 2016 and the balance sheet data as of December 31, 2015 and 2016 are derived from the audited financial statements of Antero Midstream included elsewhere in this prospectus.

 
  Year Ended
December 31,
 
 
  2015   2016  
 
  (in thousands, except
per unit amounts)

 

Revenue:

             

Revenue—Antero Resources

  $ 386,164   $ 585,517  

Revenue—third-party

    1,160     835  

Gain on sale of assets

        3,859  

Total revenue

    387,324     590,211  

Operating expenses:

             

Direct operating

    78,852     161,587  

General and administrative (before equity-based compensation)

    28,736     28,114  

Equity-based compensation

    22,470     26,049  

Depreciation

    86,670     99,861  

Contingent acquisition consideration accretion

    3,333     16,489  

Total operating expenses

    220,061     332,100  

Operating income

    167,263     258,111  

Interest expense

    (8,158 )   (21,893 )

Equity in earnings of unconsolidated affiliates

        485  

Net income

  $ 159,105   $ 236,703  

Pre-Water Acquisition net income attributed to parent

    (40,193 )    

General partner interest in net income attributable to incentive distribution rights

    (1,264 )   (16,944 )

Limited partners' interest in net income

  $ 117,648   $ 219,759  

Net income allocable to common units

  $ 62,421   $ 125,241  

Net income allocable to subordinated units

    55,227     94,518  

Limited partner interest in net income

  $ 117,648   $ 219,759  

Net income per limited partner unit—basic and diluted:

             

Common units

  $ 0.76   $ 1.24  

Subordinated units

  $ 0.73   $ 1.24  

Weighted average limited partner units outstanding:

             

Basic:

             

Common units

    82,538     100,706  

Subordinated units(1)

    75,941     75,941  

Diluted:

             

Common units

    82,586     100,860  

Subordinated units(1)

    75,941     75,941  

Balance sheet data (at period end):

             

Cash and cash equivalents

  $ 6,883   $ 14,042  

Property and equipment, net

    1,893,826     2,195,879  

Total assets

    1,980,032     2,349,895  

Long-term indebtedness

    620,000     849,914  

Total capital

    1,082,745     1,222,810  

Cash flow data:

             

Net cash provided by operating activities

  $ 259,678   $ 378,607  

Net cash used in investing activities

    (445,455 )   (478,163 )

Net cash provided by (used in) financing activities

    (37,532 )   106,715  

Other financial data:

             

Adjusted EBITDA(2)

  $ 279,736   $ 404,353  

(1)
On, February 9, 2017, in connection with the payment of Antero Midstream's fourth quarter 2016 quarterly distribution, all of the outstanding subordinated units of Antero Midstream converted into common units on a one-for-one basis.

(2)
For a discussion of the non-GAAP financial measure Adjusted EBITDA, including a reconciliation of Adjusted EBITDA to its most directly comparable financial measures calculated and presented in accordance with GAAP, please read "—Antero Midstream's Non-GAAP Financial Measures" below.

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Antero Midstream's Non-GAAP Financial Measures

        Antero Midstream views Adjusted EBITDA as an important indicator of its performance. Antero Midstream defines Adjusted EBITDA as net income before interest expense, depreciation expense, accretion of contingent acquisition consideration, equity-based compensation, equity in earnings of unconsolidated affiliates, distributions from unconsolidated affiliates and gain on sale of assets.

        Antero Midstream uses Adjusted EBITDA to assess:

    the financial performance of its assets, without regard to financing methods in the case of Adjusted EBITDA, capital structure or historical cost basis;

    its operating performance and return on capital as compared to other publicly traded partnerships in the midstream energy sector, without regard to financing or capital structure; and

    the viability of acquisitions and other capital expenditure projects.

        Antero Midstream defines Distributable Cash Flow as Adjusted EBITDA less pre-acquisition net income attributable to the parent, depreciation expense attributable to the parent, equity based compensation attributable to the parent, interest expense attributable to the parent, cash interest paid, income tax withholding payments and cash reserved for payments upon vesting of equity-based compensation awards, cash reserved for bond interest payments and ongoing maintenance capital expenditures paid, excluding pre-acquisition amounts attributable to the parent, plus cash to be received from unconsolidated affiliates. Antero Midstream uses Distributable Cash Flow as a performance metric to compare the cash generating performance of the Partnership from period to period and to compare the cash generating performance for specific periods to the cash distributions (if any) that are expected to be paid to unitholders. Distributable Cash Flow does not reflect changes in working capital balances.

        Adjusted EBITDA and Distributable Cash Flow are non-GAAP financial measures. The GAAP measure most directly comparable to Adjusted EBITDA and Distributable Cash Flow is net income. The non-GAAP financial measures of Adjusted EBITDA and Distributable Cash Flow should not be considered as alternatives to the GAAP measure of net income. Adjusted EBITDA and Distributable Cash Flow are not presentations made in accordance with GAAP and have important limitations as an analytical tool because they include some, but not all, items that affect net income and Adjusted EBITDA. You should not consider Adjusted EBITDA and Distributable Cash Flow in isolation or as a substitute for analyses of results as reported under GAAP. Our definition of Adjusted EBITDA and Distributable Cash Flow may not be comparable to similarly titled measures of other partnerships.

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        The following table represents a reconciliation of Antero Midstream's Adjusted EBITDA and Distributable Cash Flow to the most directly comparable GAAP financial measures for the periods presented:

 
  Year Ended
December 31,
 
 
  2015   2016  
 
  ($ in thousands)
 

Reconciliation of Net Income to Adjusted EBITDA and Distributable Cash Flow:

             

Net income

  $ 159,105   $ 236,703  

Interest expense

    8,158     21,893  

Depreciation expense

    86,670     99,861  

Accretion of contingent acquisition consideration

    3,333     16,489  

Equity-based compensation

    22,470     26,049  

Equity in earnings of unconsolidated affiliates

        (485 )

Distributions from unconsolidated affiliates

        7,702  

Gain on sale of assets

        (3,859 )

Adjusted EBITDA

    279,736     404,353  

Pre-Water Acquisition net income attributed to parent

    (40,193 )    

Pre-Water Acquisition depreciation expense attributed to parent

    (18,767 )    

Pre-Water Acquisition equity-based compensation expense attributed to parent          

    (3,445 )    

Pre-Water Acquisition interest expense attributed to parent

    (2,326 )    

Cash interest paid, net—attributable to Antero Midstream

   
(5,149

)
 
(13,494

)

Income tax witholding upon vesting of Antero Midstream equity-based compensation awards

    (4,806 )   (5,636 )

Cash reserved for bond interest(1)

        (10,481 )

Maintenance capital expenditures(2)

    (13,097 )   (21,622 )

Distributable cash flow

  $ 191,953   $ 353,120  

Total distributions to Antero Midstream Partners LP unitholders

  $ 132,651   $ 200,355  

(1)
Cash reserved for bond interest payments represents accrued interest expense on Antero Midstream's 5.375% senior notes outstanding during the period that is paid on a semi-annual basis on March 15th and September 15th of each year.

(2)
Maintenance capital expenditures represent that portion of Antero Midstream's estimated capital expenditures associated with (i) the connection of new wells to Antero Midstream's gathering and compression systems that Antero Midstream believes will be necessary to offset the natural production declines Antero Resources will experience on all of its wells over time and (ii) water delivery to new wells necessary to maintain the average throughput volume on Antero Midstream's systems.

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RISK FACTORS

        You should consider carefully the following risk factors, together with all of the other information included in this prospectus, in your evaluation of an investment in our common shares. Realization of any of the following risks could have a material adverse effect on our business, financial condition, cash flows and results of operations. In that case, we might not be able to pay or sustain our expected initial quarterly distribution on our common shares, the trading price of our common shares could decline and you could lose all or part of your investment.

Risks Inherent in an Investment in Us

Our cash flow will be entirely dependent upon the ability of Antero Midstream to make cash distributions on the IDRs.

        Following the completion of this offering, we will continue to own of all of the capital interests in IDR LLC, which owns all of the IDRs in Antero Midstream. Accordingly, the source of our earnings and cash flow initially will consist exclusively of cash distributions from IDR LLC, which will consist exclusively of cash distributions from Antero Midstream on the IDRs. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on the IDRs. The amount of cash that Antero Midstream will be able to distribute to its partners, including IDR LLC, each quarter principally depends upon the amount of cash it generates from its business. For a description of certain factors that can cause fluctuations in the amount of cash that Antero Midstream generates from its business, please read "—Risks Related to Antero Midstream's Business" and "Management's Discussion and Analysis of Financial Condition and Results of Operations."

        Antero Midstream may not have sufficient available cash each quarter to continue paying distributions at its current level or at all. If Antero Midstream reduces its per unit distribution, either because of reduced operating cash flow, higher expenses, increased capital requirements, increased common units outstanding (including common units issued in connection with Antero Midstream's at-the-market equity offering program) or otherwise, we will have less cash available for distribution to you and would likely be required to reduce our per share distribution to you. You should also be aware that the amount of cash Antero Midstream has available for distribution depends primarily upon Antero Midstream's cash flow, including cash flow from the release of financial reserves as well as borrowings, and is not solely a function of profitability, which will be affected by non-cash items. As a result, Antero Midstream may make cash distributions during periods when it records losses and may not make cash distributions during periods when it records profits.

        Furthermore, our ability to distribute cash received in connection with distributions on the IDRs to our shareholders is limited by a number of factors, including:

    the expenses we will incur as a result of being a publicly traded company;

    our payment of any income taxes;

    interest expense and principal payments on any future indebtedness incurred by us;

    distributions made by IDR LLC with respect to the Series B Units;

    restrictions on distributions contained in Antero Midstream's current revolving credit facility and any future debt agreements entered into by Antero Midstream or us; and

    reserves, if any, our general partner establishes for the proper conduct of our business, to comply with applicable law or any agreement binding on us or our subsidiaries (exclusive of Antero Midstream and its subsidiaries), which reserves are not subject to a limit pursuant to our partnership agreement.

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        A material increase in amounts paid or reserved with respect to any of these factors could restrict our ability to pay quarterly distributions to our shareholders.

In the future, we may not have sufficient cash to pay our estimated initial quarterly distribution or to increase distributions.

        Because our cash flow is entirely dependent of cash distributions from IDR LLC, which is dependent on cash distributions from Antero Midstream on the IDRs, the amount of distributions we are able to make to our shareholders may fluctuate based on the level of distributions Antero Midstream makes to its partners, including IDR LLC, and the level of distributions IDR LLC makes to its members, including us. We cannot assure you that Antero Midstream will continue to make quarterly distributions at its most recently declared level of $0.28 per unit or any other level, or increase its quarterly distributions in the future. In addition, while we would expect to increase or decrease distributions to our shareholders if Antero Midstream were to increase or decrease distributions, the timing and amount of such changes in distributions, if any, would not necessarily be comparable to the timing and amount of any changes in distributions made by Antero Midstream. Various factors, such as reserves established by the board of directors of our general partner (including in anticipation of increasing distributions to our unitholders to account for make-whole distributions paid by IDR LLC to the holders of newly-vested Series B Units), may affect the distributions we make to our shareholders. In addition, prior to making any distributions to our shareholders, we will reimburse our general partner and its affiliates for all direct and indirect expenses incurred by them on our behalf. Our general partner will determine the amount of these reimbursed expenses. The reimbursement of these expenses could adversely affect the amount of distributions we make to our shareholders.

        We cannot guarantee that in the future we will be able to pay distributions or that any distributions paid by Antero Midstream or IDR LLC will allow us to pay distributions at or above our estimated total quarterly cash distributions for the twelve-month period ending June 30, 2018 of $            per common share. The actual amount of cash that is available for distribution to our shareholders will depend on numerous factors, many of which are beyond our control or the control of our general partner. For additional information, please read "Our Cash Distribution Policy and Restrictions on Distributions."

The assumptions underlying the estimated cash available for distribution that we included in "Our Cash Distribution Policy and Restrictions on Distributions" are inherently uncertain and are subject to significant business, financial, regulatory and competitive risks and uncertainties that could cause actual results to differ materially from those forecasted.

        The estimated cash available for distribution set forth in "Our Cash Distribution Policy and Restrictions on Distributions" includes Antero Midstream's estimated results of operations, Adjusted EBITDA and cash available for distribution for the twelve-month period ending June 30, 2018 that will be necessary in order for us to pay the estimated aggregate cash distribution on all of our common shares during the period. We estimate that our estimated cash available for distribution for the twelve-month period ending June 30, 2018 will be approximately $48 million, as compared to approximately $0 for the year ended December 31, 2015 and $9 million for the year ended December 31, 2016, in each case on a pro forma basis. The prospective financial information has been prepared by management, and we have not received an opinion or report on it from our or any other independent auditor. The assumptions underlying the estimates are inherently uncertain and are subject to significant business, economic, financial, regulatory and competitive risks and uncertainties that could cause actual results to differ materially from those forecasted. We expect that any significant variance between our actual and estimated cash available for distribution will primarily be driven by the distribution per Antero Midstream common unit, which will vary based on Antero Midstream's cash available for distribution and the number of Antero Midstream common units outstanding. We expect that any significant variance between Antero Midstream's actual cash available for distribution during the twelve-month period ending June 30, 2018

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and estimated cash available for distribution will be primarily driven by differences between Antero Resources' development plan and actual completions and production during the period. If we do not achieve the estimated results, we may not be able to pay the full estimated cash distribution for the twelve-month period ending June 30, 2018 or any amount on common shares during such period, in which event the market price of our common shares may decline materially.

Our right to receive distributions paid by Antero Midstream on the IDRs may be limited or modified by our general partner without the consent of our shareholders, which may reduce cash distributions to you.

        We own all of the capital interests in IDR LLC, which owns all of the IDRs that entitle IDR LLC to receive increasing percentages (up to a maximum of 50%, to the extent not modified) of any cash distributed by Antero Midstream in excess of $0.1955 per Antero Midstream common unit in any quarter. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on the IDRs. All of the cash flow we receive from IDR LLC is derived from its ownership of these IDRs. Please read "Our Cash Distribution Policy and Restrictions on Distributions."

        Antero Midstream, like other publicly traded partnerships, generally will undertake an acquisition or expansion capital project only if, after giving effect to related costs and expenses, the transaction would be expected to be accretive, meaning it would increase cash distributions per unit in future periods. Because IDR LLC currently participates in the IDRs at all levels, including the highest sharing level of 50%, an acquisition or capital project generally is less likely to be accretive to the unitholders of Antero Midstream than if the IDRs were entitled to a lower incremental cash flow. IDR LLC may receive a proposal to reduce the IDRs to facilitate a particular acquisition or expansion capital project. Any such reduction of IDRs will reduce the amount of cash that otherwise would have been distributed by IDR LLC to us, which will in turn reduce the cash distributions we otherwise would be able to pay to you. Our shareholders will not be able to vote on, or otherwise prohibit our general partner from taking, similar actions in the future and our general partner may elect to modify the incentive distributions without considering the interests of our shareholders. In addition, there can be no guarantee that the expected benefits of any IDR modification will be realized.

        Additionally, IDR LLC has the right under Antero Midstream's partnership agreement, subject to certain conditions, to elect to relinquish the right to receive incentive distribution payments based on the initial target distribution levels and to reset, at higher levels, the minimum quarterly distribution amount and target distribution levels upon which the incentive distribution payments to IDR LLC would be set. In connection with the resetting of the target distribution levels and the corresponding relinquishment by IDR LLC of incentive distribution payments based on the target cash distributions prior to the reset, IDR LLC will be entitled to receive a number of newly-issued common units in Antero Midstream equal to the result of dividing (i) the aggregate amount of cash distributions made by Antero Midstream for the quarter immediately preceding the reset event by (ii) the cash distribution made by Antero Midstream in respect of each common unit for such quarter. IDR LLC's right to reset the minimum quarterly distribution amount and target distribution levels upon which the incentive distributions payable to IDR LLC are based may be exercised, subject to certain restrictions, without approval of Antero Midstream's unitholders, our shareholders or Antero Midstream's conflicts committee. The reset minimum quarterly distribution amount and target distribution levels will be higher than the minimum quarterly distribution amount and the target distribution levels prior to the reset such that IDR LLC will not receive any incentive distributions under the reset target distribution levels until cash distributions per unit following this event increase.

        IDR LLC may exercise this reset right in order to facilitate acquisitions or internal growth projects that would otherwise not be sufficiently accretive to cash distributions per common unit, taking into account the existing levels of incentive distribution payments being made to the general partner. For additional information, please read "Antero Midstream Partners LP's Cash Distribution Policy—Incentive Distribution Rights—IDR LLC's Right to Reset Incentive Distribution Levels."

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A reduction in Antero Midstream's distributions will disproportionately affect the amount of cash distributions on the IDRs.

        IDR LLC's ownership of Antero Midstream's IDRs currently entitle it to receive increasing percentages, ranging from 15% up to 50% of all cash distributed by Antero Midstream in excess of $0.1955 per common unit per quarter. Based on Antero Midstream's distribution history, IDR LLC initially will be entitled to receive 50% of all cash distributed by Antero Midstream in excess of $0.2550 per common unit per quarter. A decrease in the amount of quarterly distributions paid by Antero Midstream to $0.2550 or less per common unit would reduce IDR LLC's percentage of incremental quarterly cash distributions in excess of $0.1955 per common unit from 50% to 15%. As a result, any such reduction in quarterly cash distributions from Antero Midstream would have the effect of disproportionately reducing the amount of distributions that IDR LLC receives from Antero Midstream on the IDRs as compared to cash distributions Antero Midstream makes with respect to its common units.

If distributions on our common shares are not paid with respect to any fiscal quarter, including those at the anticipated initial distribution rate, our shareholders will not be entitled to receive any payments in respect of such quarter.

        Our distributions to our shareholders will not be cumulative. Consequently, if distributions on our common shares are not paid with respect to any fiscal quarter, including those at the anticipated initial distribution rate, our shareholders will not be entitled to receive any payments in respect of such quarter in the future.

The amount of cash that we and Antero Midstream distribute each quarter may limit our ability to grow.

        Because we and Antero Midstream each distribute all of our respective cash from operations on a quarterly basis, our growth and Antero Midstream's growth may not be as fast as the growth of businesses that continually reinvest their cash to expand ongoing operations. In fact, because our cash flow currently is generated solely from distributions we receive from IDR LLC, which are derived exclusively from the IDRs, our growth will be completely dependent upon Antero Midstream. The amount of distributions paid on the IDRs is based on the per unit distribution paid by Antero Midstream on each of its common units and the number of Antero Midstream common units outstanding. Please read "Antero Midstream Partners LP's Cash Distribution Policy." If we issue additional common shares or incur debt, the payment of distributions on those additional common shares or interest on that debt could increase the risk that we will be unable to maintain or increase our cash distribution levels.

Our rate of distribution growth may be reduced to the extent we purchase equity interests from Antero Midstream, which will reduce the relative percentage of the cash we receive from the IDRs.

        Our business strategy includes, where appropriate, supporting the growth of Antero Midstream by making loans, purchasing equity interests or providing other forms of financial support to Antero Midstream to fund an acquisition of a business or asset or another growth project. To the extent we purchase equity interests from Antero Midstream that are not entitled to distributions or do not receive distributions at the same rates as the IDRs, the rate of our distribution growth may be reduced, at least in the short term, as less of our cash distributions will come from our ownership of IDRs, whose distributions increase at a faster rate than Antero Midstream's common units and any similar equity interests Antero Midstream may issue in the future.

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Restrictions in Antero Midstream's existing and future debt agreements could limit Antero Midstream's ability to make distributions to IDR LLC, and therefore IDR LLC's ability to make distributions to us, which in turn would limit our ability to make distributions on our common shares.

        Antero Midstream's revolving credit facility and the indenture governing Antero Midstream's outstanding senior notes contain various operating and financial restrictions and covenants. Antero Midstream's ability to comply with these restrictions and covenants may be affected by events beyond its control, including prevailing economic, financial and industry conditions. If Antero Midstream is unable to comply with these restrictions and covenants, any indebtedness under this credit facility may become immediately due and payable and Antero Midstream's lenders' commitment to make further loans under this credit facility may terminate. Antero Midstream might not have, and might be unable to obtain, sufficient funds to satisfy these accelerated payment obligations.

        Antero Midstream's payment of principal and interest on any indebtedness will reduce its cash distributions on the IDRs, thereby reducing our cash available for distribution on our common shares. Antero Midstream's revolving credit facility and the indenture governing Antero Midstream's outstanding senior notes will limit our ability to pay distributions to our shareholders during an event of default or if an event of default would result from the distribution.

        For more information regarding Antero Midstream's debt agreements, please read "Management's Discussion and Analysis of Financial Condition and Results of Operations—Antero Midstream's Capital Resources and Liquidity." For more information regarding risks related to Antero Midstream's debt agreements, please see "—Risks Related to Antero Midstream's Business—"Restrictions in Antero Midstream's revolving credit facility and its other debt agreements could adversely affect its business, financial condition, results of operations and ability to make quarterly cash distributions to its unitholders."

Our partnership agreement restricts the rights of shareholders owning 20% or more of our shares.

        Our shareholders' voting rights are restricted by the provision in our partnership agreement generally providing that any shares held by a person or group that owns 20% or more of any class of shares then outstanding, other than our general partner, the Sponsors (or certain transferees in private, non-exchange transactions), their respective affiliates and persons who acquired such shares with the prior approval of our general partner's board of directors, cannot be voted on any matter. In addition, our partnership agreement contains provisions limiting the ability of our shareholders to call meetings or to acquire information about our operations, as well as other provisions limiting our shareholders' ability to influence the manner or direction of our management. As a result, the price at which our common shares will trade may be lower because of the absence or reduction of a takeover premium in the trading price.

Our shareholders will not elect or have the power to remove our general partner and will not vote in the election of our general partner's directors. Upon the completion of this offering, the Sponsors will own a sufficient number of common shares to allow them to prevent the removal of our general partner.

        Our shareholders only have limited voting rights on matters affecting our business and, therefore, limited ability to influence management's decisions regarding our business. The board of directors of our general partner, including our independent directors, will be designated and elected by the Sponsors or their designees. Our remaining shareholders will not have the ability to elect our general partner or the members of the board of directors of our general partner. Additionally, as a result of our resulting governance arrangements and the 20% voting limitation in our partnership agreement, it will be difficult for one or more of our shareholders to gain control of our general partner's board of directors. Please read "Management—Designation of Directors."

        In addition, if our shareholders are dissatisfied with the performance of our general partner, they will have little ability to remove our general partner. Our general partner may not be removed unless that

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removal is for cause and is approved by the holders of at least 80% of our outstanding shares. At the completion of this offering and assuming no exercise of the underwriters' option to purchase additional common shares, the Sponsors will collectively own        % of our outstanding common shares. This ownership level will enable the Sponsors to prevent our general partner's removal. Please read "Description of Our Partnership Agreement—Withdrawal or Removal of the General Partner."

        As a result of these provisions, the price at which our common shares will trade may be lower because of the absence or reduction of a takeover premium in the trading price.

You will experience immediate and substantial dilution of $            per common share in the net tangible book value of your common shares.

        The initial public offering price of our common shares is substantially higher than the pro forma net tangible book value per share immediately after the offering. If you purchase common shares in this offering you will incur immediate and substantial dilution in the pro forma net tangible book value per share from the price you pay for the common shares. Please read "Dilution."

Our general partner may cause us to issue additional common shares, including in connection with the redemption of Series B Units, or other equity securities, as well as issue equity securities that are senior to our common shares, without your approval, which may adversely affect you.

        Our general partner may cause us to issue an unlimited number of additional common shares, including in connection with the redemption of Series B Units, or other equity securities of equal rank with the common shares, without shareholder approval. For additional information regarding the issuance of our common shares in connection with the redemption of Series B Units, please read "Certain Relationships and Related Party Transactions—Limited Liability Company Agreement of IDR LLC." In addition, we may issue an unlimited number of shares that are senior to our common shares in right of distribution, liquidation and voting. The issuance of additional common units or our other equity securities of equal or senior rank, will have the following effects:

    each shareholder's proportionate ownership interest in us may decrease;

    the amount of cash available for distribution on each common share may decrease;

    the relative voting strength of each previously outstanding common share may be diminished;

    the ratio of taxable income to distributions may increase; and

    the market price of the common shares may decline.

        Please read "Description of Our Partnership Agreement—Issuance of Additional Securities."

If Antero Midstream's unitholders remove AMP GP as the general partner of Antero Midstream, AMP GP would be required to sell or exchange its general partner interest, and we would lose the ability to manage and control Antero Midstream.

        At the closing of this offering and as a result of the Reorganization, we will own, and appoint all of the members of the board of directors of, AMP GP, which will own the non-economic general partner interest in Antero Midstream. AMP GP may not be removed as general partner of Antero Midstream unless that removal is for cause and is approved by the vote of the holders of not less than 662/3% of the outstanding units of Antero Midstream, voting together as a single class, including units held by AMP GP and its affiliates, and Antero Midstream receives an opinion of counsel regarding limited liability and tax matters. Any removal of AMP GP is also subject to the approval of a successor general partner by the vote of the holders of a majority of the outstanding Antero Midstream common units, voting as a class. The ownership of more than 331/3% of the outstanding units by AMP GP and its affiliates gives them the ability to prevent our general partner's removal. In the event of the removal of AMP GP as general partner of Antero

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Midstream or its withdrawal as general partner in violation of Antero Midstream's partnership agreement, a successor general partner will have the option to purchase AMP GP's general partner interest for a cash payment equal to the fair market value of that interest. Under all other circumstances where AMP GP withdraws as general partner of Antero Midstream, AMP GP will have the option to require the successor general partner to purchase the general partner interest of Antero Midstream for fair market value. In each case, this fair market value will be determined by agreement between AMP GP and the successor general partner. If no agreement is reached, an independent investment banking firm or other independent expert selected by AMP GP and the successor general partner will determine the fair market value. If, however, AMP GP and the successor general partner cannot agree upon an expert, then an expert chosen by agreement of the experts selected by each of them will determine the fair market value. In each case, AMP GP would also lose its ability to manage Antero Midstream. Please read "Material Provisions of the Partnership Agreement of Antero Midstream Partners LP"

        In addition, if AMP GP is removed as general partner of Antero Midstream, we would face an increased risk of being deemed an investment company. Please read "—If in the future we cease to manage and control Antero Midstream, we may be deemed to be an investment company under the Investment Company Act of 1940."

You may not have limited liability if a court finds that shareholder action constitutes control of our business.

        Under Delaware law, you could be held liable for our obligations to the same extent as a general partner if a court determined that the right or the exercise of the right by our shareholders as a group to remove or replace our general partner, to approve some amendments to the partnership agreement or to take other action under our partnership agreement constituted participation in the "control" of our business. Additionally, the limitations on the liability of holders of limited partner interests for the liabilities of a limited partnership have not been clearly established in many jurisdictions.

        Furthermore, Section 17-607 of the Delaware Revised Uniform Limited Partnership Act provides that, under some circumstances, a shareholder may be liable to us for the amount of a distribution for a period of three years from the date of the distribution. Please read "Description of Our Partnership Agreement—Limited Liability" for a discussion of the implications of the limitations on liability to a shareholder.

If in the future we cease to manage and control Antero Midstream, we may be deemed to be an investment company under the Investment Company Act of 1940.

        If we cease to manage and control Antero Midstream or IDR LLC and are deemed to be an investment company under the Investment Company Act of 1940, as amended (the "Investment Company Act"), we would either have to register as an investment company under the Investment Company Act, obtain exemptive relief from the SEC or modify our organizational structure or our contractual rights or asset mix to fall outside the definition of an investment company. Registering as an investment company could, among other things, materially limit our ability to engage in transactions with affiliates, including the purchase and sale of certain securities or other property to or from our affiliates, restrict our ability to borrow funds or engage in other transactions involving leverage, require us to add additional directors who are independent of us and our affiliates, and adversely affect the price of our common shares.

The price of our common shares may be volatile, and a trading market that will provide you with adequate liquidity may not develop.

        Prior to this offering there has been no public market for our common shares. An active market for our common shares may not develop or may not be sustained after this offering. The initial public offering price of our common shares will be determined by negotiations between the selling shareholder and the underwriters, based on several factors that we discuss in the "Underwriting" section of this prospectus.

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This price may not be indicative of the market price for our common shares after this initial public offering. The market price of our common shares could be subject to significant fluctuations after this offering, and may decline below the initial public offering price. You may be unable to resell your common shares at or above the initial public offering price. The following factors, among others, could affect our common share price:

    Antero Midstream's operating and financial performance and prospects and the trading price of its common units;

    the level of Antero Midstream's quarterly distributions and our quarterly distributions;

    quarterly variations in the rate of growth of our financial indicators, such as distributable cash flow per common share, net income and revenues;

    changes in revenue or earnings estimates or publication of research reports by analysts;

    speculation by the press or investment community;

    sales of our common shares by our shareholders;

    the exercise by the Series B Holders of their redemption rights with respect to any vested Series B Units;

    announcements by Antero Midstream or its competitors of significant contracts, acquisitions, strategic partnerships, joint ventures, securities offerings or capital commitments;

    general market conditions;

    changes in accounting standards, policies, guidance, interpretations or principles;

    adverse changes in tax laws or regulations;

    domestic and international economic, legal and regulatory factors related to Antero Midstream's performance; and

    other factors described in these "Risk Factors."

Our common shares and Antero Midstream's common units may not trade in relation or proportion to one another.

        Our common shares and Antero Midstream's common units may not trade in simple relation or proportion to one another. Instead, while the trading prices of our common shares and Antero Midstream's common units are likely to follow generally similar broad trends, the trading prices may diverge because, among other things:

    with respect to the first $0.1955 of distributable cash flow per common unit, Antero Midstream's cash distributions to its unitholders have a priority over distributions on its IDRs;

    our cash flow is more volatile than the cash flow paid to Antero Midstream's unitholders because we participate in tiered incentive distributions associated with the IDRs in Antero Midstream while Antero Midstream's unitholders participate in all distributions made by Antero Midstream;

    IDR LLC will distribute a portion of the cash it receives from Antero Midstream to the holders of outstanding Series B Units;

    we expect to pay federal and state income taxes in the future; and

    we may enter into other businesses separate and apart from Antero Midstream or any of its affiliates.

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An increase in interest rates may cause the market price of our common shares to decline.

        Like all equity investments, an investment in our common shares is subject to certain risks. In exchange for accepting these risks, investors may expect to receive a higher rate of return than would otherwise be obtainable from lower-risk investments. Accordingly, as interest rates rise, the ability of investors to obtain higher risk-adjusted rates of return by purchasing government-backed debt securities may cause a corresponding decline in demand for riskier investments generally, including yield-based equity investments such as publicly traded limited partnership interests. Reduced demand for our common shares resulting from investors seeking other more favorable investment opportunities may cause the trading price of our common shares to decline.

Future sales of our common shares in the public market could reduce our common share price, and any additional capital raised by us through the sale of equity or convertible securities may dilute your ownership in us.

        Subject to certain limitations and exceptions, each Series B Holder may require IDR LLC to redeem all or a part of such holder's vested Series B Units for common shares in us at a ratio described in the IDR LLC Agreement, subject to customary conversion rate adjustments for equity splits, equity dividends and reclassification and other similar transactions, and then sell those common shares. For more information on the Redemption Right, please read "Certain Relationships and Related Party Transactions—Limited Liability Company Agreement of IDR LLC." We may also issue additional common shares or convertible securities in subsequent public or private offerings. We cannot predict the size of future issuances of our common shares or securities convertible into common shares or the effect, if any, that future issuances and sales of our common shares will have on the market price of our common shares. Sales of substantial amounts of our common shares (including shares issued in connection with an acquisition), or the perception that such sales could occur, may adversely affect prevailing market prices of our common shares.

The underwriters of this offering may waive or release parties to the lock-up agreements entered into in connection with this offering, which could adversely affect the price of our common shares.

        The selling shareholder, we and the directors and executive officers of our general partner will enter into lock-up agreements with respect to any sale of their common shares (following a redemption), pursuant to which they are subject to certain resale restrictions for a period of 180 days following the effective date of the registration statement of which this prospectus forms a part. The representatives of the underwriters to this offering, at any time and without notice, may release all or any portion of the common shares subject to the foregoing lock-up agreements. If the restrictions under the lock-up agreements are waived, then the applicable common shares will be available for sale into the public markets, which could cause the market price of our common shares to decline and impair our ability to raise capital.

The Sponsors hold a majority of the voting power of our common shares.

        Immediately following this offering, the Sponsors will hold approximately        % of the voting power of our common shares (or         % if the underwriters exercise their option to purchase additional common shares in full). The Sponsors are entitled to act separately in their own respective interests with respect to their partnership interests in us, and will have the ability to elect all of the members of our board of directors. Please read "Management—Designation of Directors." In addition, they will be able to determine the outcome of all matters requiring shareholder approval, including certain mergers and other material transactions, and will be able to cause or prevent a change in the composition of our board of directors or a change in control of our company that could deprive our shareholders of an opportunity to receive a premium for their common shares as part of a sale of our company. So long as the Sponsors continue to own a significant amount of our outstanding shares, even if such amount is less than 50%, they

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will continue to be able to strongly influence all matters requiring shareholder approval, regardless of whether or not other shareholders believe that the transaction is in their own best interests.

For as long as we are an emerging growth company, we will not be required to comply with certain reporting requirements, including those relating to accounting standards and disclosure about our executive compensation, that apply to other public companies.

        The JOBS Act contains provisions that, among other things, relax certain reporting requirements for "emerging growth companies," including certain requirements relating to accounting standards and compensation disclosure. We are classified as an emerging growth company. For as long as we are an emerging growth company, which may be up to five full fiscal years, unlike other public companies, we will not be required to, among other things, (1) provide an auditor's attestation report on management's assessment of the effectiveness of our system of internal control over financial reporting pursuant to Section 404(b) of the Sarbanes Oxley Act of 2002, (2) comply with any new requirements adopted by the PCAOB requiring mandatory audit firm rotation or a supplement to the auditor's report in which the auditor would be required to provide additional information about the audit and the financial statements of the issuer, (3) comply with any new audit rules adopted by the PCAOB after April 5, 2012 unless the SEC determines otherwise, (4) provide certain disclosure regarding executive compensation required of larger public companies or (5) hold shareholder advisory votes on executive compensation.

If we or Antero Midstream fail to develop or maintain an effective system of internal controls, our ability to accurately report our financial results or prevent fraud could be adversely affected. As a result, our shareholders could lose confidence in our financial reporting, which would harm our business and the trading price of our common shares.

        Effective internal controls are necessary for us to provide reliable financial reports, prevent fraud and operate successfully as a publicly traded company. We are not currently required to comply with the SEC's rules implementing Section 404 of the Sarbanes-Oxley Act of 2002, and are therefore not required to make a formal assessment of the effectiveness of our internal control over financial reporting for that purpose. Upon becoming a publicly traded company, we will be required to comply with the SEC's rules implementing Sections 302 and 404 of the Sarbanes-Oxley Act of 2002, which will require our management to certify financial and other information in our quarterly and annual reports and provide an annual management report on the effectiveness of our internal control over financial reporting. Though we will be required to disclose material changes made to our internal controls and procedures on a quarterly basis, we will not be required to make our first annual assessment of our internal control over financial reporting pursuant to Section 404 until the year following our first annual report required to be filed with the SEC. To comply with the requirements of being a publicly traded company, we will need to implement additional internal controls, reporting systems and procedures. If we or Antero Midstream cannot provide reliable financial reports or prevent fraud, our and Antero Midstream's reputation and operating results will be harmed. We cannot be certain that our efforts to develop and maintain our internal controls will be successful. Any failure to develop or maintain effective internal controls, or difficulties encountered in implementing or improving our internal controls, could harm our and Antero Midstream's operating results or cause us or Antero Midstream to fail to meet our reporting obligations. Ineffective internal controls could also cause investors to lose confidence in our reported financial information, which would likely have a negative effect on the trading price of our common shares and Antero Midstream's common units.

The NYSE does not require a limited partnership like us to comply with certain of its corporate governance requirements.

        Because we are a limited partnership, the NYSE does not require our general partner to have a majority of independent directors on its board of directors or to establish a compensation committee or a

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nominating and corporate governance committee. Accordingly, our shareholders will not have the same protections afforded to certain corporations that are subject to all of the NYSE corporate governance requirements. In addition, as a limited partnership we are not required to seek shareholder approval for issuances of common shares, including issuances in excess of 20% of our outstanding equity securities, or for issuances of equity to certain affiliates.

We may incur liability as a result of our ownership of Antero Midstream's general partner.

        Under Delaware law, a general partner of a limited partnership is generally liable for the debts and liabilities of the partnership for which it serves as general partner, subject to the terms of any indemnification agreements contained in the partnership agreement and except to the extent the partnership's contracts are non-recourse to the general partner. As a result of our structure, we own all of the interests in and appoint all of the members of the board of directors of the general partner of Antero Midstream. To the extent the indemnification provisions in the applicable partnership agreement or non-recourse provisions in our contracts are not sufficient to protect us from such liability, we may in the future incur liabilities as a result of our ownership of AMP GP. Please read "Conflicts of Interest and Fiduciary Duties."

Our general partner interest or the control of our general partner may be transferred to a third party without shareholder consent.

        Our general partner may transfer its general partner interest to a third party, including in a merger or in a sale of all or substantially all of its assets, without the consent of our shareholders. Furthermore, the Sponsors may transfer all or a portion of their ownership interests in our general partner to a third party, also without shareholder consent. The new owners of our general partner would then be in a position to replace the board of directors and officers of our general partner with its own designees and thereby exert significant control over the decisions made by the board of directors and officers.

The future debt that we incur may limit the distributions that we can pay to our shareholders.

        Our payment of principal and interest on any future indebtedness will reduce our cash available for distribution to our shareholders. We anticipate that any credit facility we enter into in the future would limit our ability to pay distributions to our shareholders during an event of default or if an event of default would result from the distributions.

        Moreover, any future indebtedness may adversely affect our ability to obtain additional financing for future operations or capital needs, limit our ability to pursue other business opportunities, or make our results of operations more susceptible to adverse economic or operating conditions.

The amount of cash distributions that we will be able to distribute to our shareholders will be reduced by the incremental costs associated with our being a publicly traded company, other general and administrative expenses and any reserves that our general partner believes it is prudent to maintain for the proper conduct of our business and for future distributions.

        Before we can pay distributions to our shareholders, we will first pay our expenses, including the costs of being a publicly traded company, which we expect to be approximately $         million per year, and taxes and other expenses, and may establish reserves for debt service requirements, if any, for future distributions during periods of limited cash flows or for other purposes.

Risks Related to Conflicts of Interest

        Our existing organizational structure and the relationships among us, Antero Midstream, our respective general partners, Antero Resources, the Sponsors and affiliated entities present the potential for conflicts of interest. Moreover, additional conflicts of interest may arise in the future among us and the

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entities affiliated with any general partner or similar interests we acquire or among Antero Midstream and such entities. For a further discussion of conflicts of interest that may arise, please read "Conflicts of Interest and Fiduciary Duties."

Conflicts of interest may arise as a result of our organizational structure and the relationships among us, Antero Midstream, our respective general partners, Antero Resources and other affiliated entities.

        Our partnership agreement defines the duties of our general partner (and, by extension, its officers and directors). Our general partner's board of directors or its conflicts committee will have authority on our behalf to resolve any conflict involving us and they have broad latitude to consider the interests of all parties to the conflict.

        Conflicts of interest may arise between us and our shareholders, on the one hand, and our general partner and affiliated entities, on the other hand, or between us and our shareholders, on the one hand, and Antero Midstream and its unitholders, on the other hand. For a description of circumstances in which conflicts could arise, please read "Conflicts of Interest and Fiduciary Duties—Potential for Conflicts." The resolution of these conflicts may not always be in our best interest or that of our shareholders.

Our partnership agreement defines our general partner's duties to us and contains provisions that reduce the remedies available to our shareholders for actions that might otherwise be challenged as breaches of fiduciary or other duties under state law.

        Our partnership agreement contains provisions that substantially reduce the standards to which our general partner would otherwise be held by state fiduciary duty law. For example, our partnership agreement:

    permits our general partner to make a number of decisions in its individual capacity, as opposed to in its capacity as our general partner. This entitles our general partner to consider only the interests and factors that it desires, and it has no duty or obligation to give any consideration to any interest of, or factors affecting, us, the Sponsors, our affiliates or any limited partner. Examples include the exercise of its limited call right, its rights to transfer or vote any shares it may own, and its determination whether or not to consent to any merger or consolidation of our partnership or amendment to our partnership agreement;

    generally provides that our general partner will not have any liability to us or our shareholders for decisions made in its capacity as a general partner so long as it acted in good faith which, pursuant to our partnership agreement, requires a subjective belief that the determination, or other action or anticipated result thereof is in, or not opposed to, our best interests;

    generally provides that any resolution or course of action adopted by our general partner and its affiliates in respect of a conflict of interest will be permitted and deemed approved by all of our shareholders, and will not constitute a breach of our partnership agreement or any duty stated or implied by law or equity if the resolution or course of action in respect of such conflict of interest is:

    approved by a majority of the members of our general partner's conflicts committee after due inquiry, based on a belief that the course of action or determination that is the subject of such approval is not adverse to us;

    approved by majority vote of our common shares (excluding shares owned by our general partner and its affiliates, but including shares owned by the Sponsors) voting together as a single class;

    provides that, to the fullest extent permitted by law, in connection with any action or inaction of, or determination made by, our general partner or the conflicts committee of our general partner's board of directors with respect to any matter relating to us, it shall be presumed that our general

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      partner or the conflicts committee of our general partner's board of directors acted in a manner that satisfied the contractual standards set forth in our partnership agreement, and in any proceeding brought by any limited partner or by or on behalf of such limited partner or any other limited partner or our partnership challenging any such action or inaction of, or determination made by, our general partner, the person bringing or prosecuting such proceeding shall have the burden of overcoming such presumption; and

    provides that our general partner and its officers and directors will not be liable for monetary damages to us, our limited partners or assignees for any acts or omissions unless there has been a final and non-appealable judgment entered by a court of competent jurisdiction determining that our general partner or those other persons acted in bad faith or, in the case of a criminal matter, acted with knowledge that such person's conduct was criminal.

        Please read "Conflicts of Interest and Fiduciary Duties."

The Sponsors may have interests that conflict with holders of our common shares.

        Immediately following this offering (assuming that the underwriters do not exercise their option to purchase additional common shares), the Sponsors will own        % of our outstanding shares and a portion of the Series B Units in IDR LLC. In addition, certain of the Sponsors own a portion of Antero Midstream's common units and Antero Resources' common stock. As a result, the Sponsors may have conflicting interests with holders of our common shares.

        Furthermore, conflicts of interest could arise in the future between us, on the one hand, and the Sponsors, on the other hand, concerning among other things, a decision whether to modify or limit the IDRs in the future or potential competitive business activities or business opportunities. These conflicts of interest may not be resolved in our favor.

Antero Resources does not own our general partner and is under no obligation to adopt a business strategy that favors us.

        The directors and officers of Antero Resources have a fiduciary duty to make decisions in the best interests of the owners of Antero Resources, which may be contrary to our interests. Antero Resources has dedicated acreage to, and entered into long-term contracts for gathering and compression services on, Antero Midstream's gathering and compression systems, as well as long-term contracts for receiving water services. However, while Antero Midstream has a 20-year right of first offer to provide processing and fractionation services to Antero Resources, subject to certain exceptions, Antero Resources is under no obligation to consider whether any future drilling plans would create beneficial opportunities for Antero Midstream. Additionally, although Antero Midstream's water services agreement and the processing and fractionation services provided by the Joint Venture are supported by minimum volume commitments, Antero Midstream's gathering and compression agreement includes minimum volumes commitments only on high-pressure pipelines and compressor stations constructed at Antero Resources' request after the Antero Midstream IPO. A reduction in the current levels of throughput volumes on Antero Midstream's gathering and compression systems by Antero Resources could have a material adverse effect on Antero Midstream's business, financial condition, results of operations and ability to make quarterly cash distributions to its unitholders, including us.

Our general partner's affiliates and the Sponsors may compete with us.

        Our partnership agreement provides that our general partner will be restricted from engaging in any business activities other than acting as our general partner and those activities incidental to its ownership of interests in us. The restrictions contained in our general partner's limited liability company agreement are subject to a number of exceptions. Affiliates of our general partner and the Sponsors will not be prohibited from engaging in other businesses or activities that might be in direct competition with us

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except to the extent they compete using our confidential information. For additional information regarding these agreements, please read "Certain Relationships and Related Party Transactions"

Our general partner has a call right that may require you to sell your common shares at an undesirable time or price.

        If at any time more than 80% of our outstanding common shares on a combined basis (including common shares issued in connection with the redemption of Series B Units) are owned by our general partner, the Sponsors (or certain transferees) or their respective affiliates, our general partner will have the right (which it may assign to any of its affiliates, the Sponsors or us), but not the obligation, to acquire all, but not less than all, of the remaining common shares held by public shareholders at a price equal to the greater of (x) the current market price of such shares as of the date three days before notice of exercise of the call right is first mailed and (y) the highest price paid by our general partner, the Sponsors (or certain transferees in private, non-exchange transactions) or their respective affiliates for such shares during the 90 day period preceding the date such notice is first mailed. As a result, you may be required to sell your common shares at an undesirable time or price and may not receive any return of or on your investment. You may also incur a tax liability upon a sale of your common shares. Upon completion of this offering, the Sponsors will own        % of the common shares. For additional information about the call right, please read "Description of Our Partnership Agreement—Limited Call Right."

Risks Related to Antero Midstream's Business

Because substantially all of Antero Midstream's revenue is derived from Antero Resources and Antero Resources' capital decisions drive our operations, any development that materially and adversely affects Antero Resources' operations, financial condition or market reputation could have a material and adverse impact on us.

        Antero Midstream is substantially dependent on Antero Resources as its primary customer, and Antero Midstream expects to derive a substantial majority of its revenues from Antero Resources for the foreseeable future. As a result, any event, whether in Antero Midstream's area of operations or otherwise, that adversely affects Antero Resources' production, drilling and completion schedule, financial condition, leverage, market reputation, liquidity, results of operations or cash flows may adversely affect Antero Midstream's revenues and cash available for distribution. Accordingly, Antero Midstream is indirectly subject to the business risks of and operating decisions made by Antero Resources, including, among others:

    a reduction in or slowing of Antero Resources' development program, which would directly and adversely impact demand for Antero Midstream's gathering, compression, processing, fractionation and water services, including services provided through its interest in the Joint Venture;

    a reduction in or slowing of Antero Resources' completions of wells, which would directly and adversely impact demand for Antero Midstream's water services;

    the volatility of natural gas, NGLs and oil prices, which could have a negative effect on the value of Antero Resources' properties, its drilling programs or its ability to finance its operations;

    the availability of capital on an economic basis to fund Antero Resources' exploration and development activities and Antero Midstream's capital expenditure programs;

    Antero Resources' ability to replace reserves;

    Antero Resources' ability to successfully integrate its recent acquisition of properties from a third party, and their successful development of such acquired acreage;

    Antero Resources' drilling and operating risks, including potential environmental liabilities;

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    Antero Resources' potential inability to enter into new hedge contracts in the future at favorable pricing or for a sufficient amount, and the potential counterparty risk relating to Antero Resources' hedging transactions;

    transportation capacity constraints and interruptions;

    adverse effects of governmental and environmental regulation; and

    losses from pending or future litigation.

        Changes in commodity prices can significantly affect Antero Midstream's capital resources, liquidity and expected operating results.

        For more information regarding the business risks Antero Resources faces and their potential impact on Antero Midstream's business, please read "—Because of the natural decline in production from existing wells, Antero Midstream's success depends, in part, on Antero Resources' ability to replace declining production and Antero Midstream's ability to secure new sources of natural gas from Antero Resources or third parties. Additionally, Antero Midstream's water services are directly associated with Antero Resources' well completion activities, the volumes of produced water from such activities and water needs, which are partially driven by horizontal lateral lengths and the number of completion stages per well. Any decrease in volumes of natural gas and produced water that Antero Resources produces or any decrease in the number of wells that Antero Resources completes could adversely affect Antero Midstream's business and operating results."

        In late 2014, global energy commodity prices declined precipitously as a result of several factors, including an increase in worldwide commodity supplies, a stronger U.S. dollar, relatively mild weather in large portions of the U.S. during the 2014 and 2015 winter months, and strong competition among oil producing countries for market share. Depressed commodity prices continued into 2015 and 2016, although a modest recovery has occurred in late 2016 and early 2017.

        Spot prices for WTI declined significantly since June 2014 levels of approximately $106.00 per Bbl and have ranged from less than $30.00 per Bbl in February 2016 to approximately $53.00 per Bbl in February 2017. Spot prices for Henry Hub natural gas also declined significantly from approximately $4.40 per MMBtu in January 2014 to $2.00 per MMBtu in March 2016. Natural gas prices have recently recovered to approximately $3.00 per MMBtu in February 2017 due to increases in demand as a result of colder winter weather in many regions of the United States. Spot prices for propane, which is the largest portion of Antero Midstream's NGLs sales, declined from approximately $1.55 per gallon in January 2014 to less than $0.35 per gallon in January 2016. Prices for propane have recovered to over $0.70 per gallon in February 2017.

        Further, Antero Midstream is subject to the risk of non-payment or non-performance by Antero Resources, including with respect to Antero Midstream's gathering, compression, processing, fractionation and water services arrangements. Antero Midstream cannot predict the extent to which Antero Resources' business would be impacted if conditions in the energy industry deteriorate, nor can Antero Midstream estimate the impact such conditions would have on Antero Resources' ability to execute its drilling and development program or perform under Antero Midstream's gathering, compression, processing, fractionation and water services arrangements. Any material non-payment or non-performance by Antero Resources could reduce Antero Midstream's ability to make distributions to its unitholders.

        Also, due to Antero Midstream's relationship with Antero Resources, Antero Midstream's ability to access the capital markets, or the pricing or other terms of any capital markets transactions, may be adversely affected by any impairment to Antero Resources' financial condition or adverse changes in its credit ratings.

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        Any material limitation on Antero Midstream's ability to access capital as a result of such adverse changes at Antero Resources could limit Antero Midstream's ability to obtain future financing under favorable terms, or at all, or could result in increased financing costs in the future. Similarly, material adverse changes at Antero Resources could negatively impact Antero Midstream's unit price, limiting Antero Midstream's ability to raise capital through equity issuances or debt financing, or could negatively affect Antero Midstream's ability to engage in, expand or pursue its business activities, and could also prevent Antero Midstream from engaging in certain transactions that might otherwise be considered beneficial to Antero Midstream.

The amount of cash Antero Midstream can distribute on its units principally depends upon the amount of cash Antero Midstream generates from its operations, which will fluctuate from quarter to quarter.

        The amount of cash Antero Midstream can distribute on its units principally depends upon the amount of cash Antero Midstream generate from its operations, which will fluctuate from quarter to quarter based on, among other things:

    the volume of water Antero Midstream handles and treats in connection with well completion operations and the volume of natural gas Antero Midstream's gather and compress;

    the volume of condensate Antero Midstream gathers;

    the volume of flowback and produced water generated by Antero Resources;

    the rates charged to third parties, if any, for Antero Midstream's gathering, compression, processing, fractionation and water services;

    market prices of natural gas, NGLs and oil and their effect on Antero Resources' drilling schedule as well as produced volumes;

    Antero Resources' ability to fund its drilling program;

    adverse weather conditions;

    the level of Antero Midstream's operating, maintenance and general and administrative costs;

    regulatory action affecting the supply of, or demand for, natural gas, the rates Antero Midstream can charge for its services, how Antero Midstream contracts for services, Antero Midstream's existing contract, its operating costs or its operating flexibility; and

    prevailing economic conditions.

        In addition, the actual amount of cash Antero Midstream will have available for distribution will depend on other factors, including:

    the level and timing of maintenance and expansion capital expenditures Antero Midstream makes;

    Antero Midstream's debt service requirements and other liabilities;

    Antero Midstream's ability to borrow under its debt agreements to pay distributions;

    fluctuations in Antero Midstream's working capital needs;

    restrictions on distributions contained in any of Antero Midstream's debt agreements;

    the cost of acquisitions, if any;

    fees and expenses of Antero Midstream's general partner and its affiliates (including Antero Resources) we are required to reimburse;

    the amount of cash reserves established by Antero Midstream's general partner; and

    other business risks affecting Antero Midstream's cash levels.

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Because of the natural decline in production from existing wells, Antero Midstream's success depends, in part, on Antero Resources' ability to replace declining production and Antero Midstream's ability to secure new sources of natural gas from Antero Resources or third parties. Additionally, Antero Midstream's water services are directly associated with Antero Resources' well completion activities, the volumes of produced water from such activities and water needs, which are partially driven by horizontal lateral lengths and the number of completion stages per well. Any decrease in volumes of natural gas that Antero Resources produces or any decrease in the number of wells that Antero Resources completes could adversely affect Antero Midstream's business and operating results.

        The natural gas volumes that support Antero Midstream's gathering and compression business depend on the level of production from natural gas wells connected to Antero Midstream's systems, which may be less than expected and will naturally decline over time. To the extent Antero Resources reduces its development activity or otherwise ceases to drill and complete wells, revenues for Antero Midstream's gathering, compression, processing, fractionation and water services will be directly and adversely affected. Antero Midstream's ability to maintain water services revenues is substantially dependent on continued completion activity by Antero Resources or third parties over time, as well as the volumes of produced water from such activity. In addition, natural gas volumes from completed wells will naturally decline and Antero Midstream's cash flows associated with these wells will also decline over time. In order to maintain or increase throughput volumes on Antero Midstream's gathering systems, Antero Midstream must obtain new sources of natural gas from Antero Resources or third parties. The primary factors affecting Antero Midstream's ability to obtain additional sources of natural gas include (i) the success of Antero Resources' drilling activity in Antero Midstream's areas of operation, (ii) Antero Resources' acquisition of additional acreage and (iii) Antero Midstream's ability to obtain dedications of acreage from third parties. Antero Midstream's fresh water delivery services, which make up a substantial portion of our water services revenues, will be in greatest demand in connection with completion activities. To the extent that Antero Resources or other fresh water delivery customers complete wells with shorter lateral lengths, the demand for Antero Midstream's fresh water delivery services would be reduced.

        Antero Midstream has no control over Antero Resources' or other producers' levels of development and completion activity in Antero Midstream's areas of operation, the amount of reserves associated with wells connected to Antero Midstream's systems or the rate at which production from a well declines. In addition, Antero Midstream's fresh water delivery business is dependent upon active development in Antero Midstream's areas of operation. In order to maintain or increase throughput volumes on Antero Midstream's fresh water delivery systems, Antero Midstream must service new wells. Antero Midstream has no control over Antero Resources or other producers or their development plan decisions, which are affected by, among other things:

    the availability and cost of capital;

    prevailing and projected natural gas, NGLs and oil prices;

    demand for natural gas, NGLs and oil;

    levels of reserves;

    geologic considerations;

    environmental or other governmental regulations, including the availability of drilling permits and the regulation of hydraulic fracturing; and

    the costs of producing the gas and the availability and costs of drilling rigs and other equipment.

        Fluctuations in energy commodity prices can also greatly affect the development of reserves. For additional detail on the recent fluctuations in energy commodity prices, please see "Because substantially all of Antero Midstream's revenue is derived from Antero Resources and Antero Resources' capital decisions drive our operations, any development that materially and adversely affects Antero Resources' operations, financial condition or market reputation could have a material and adverse impact on us."

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These lower prices have compelled most natural gas and oil producers, including Antero Resources, to reduce the level of exploration, drilling and production activity. This will have a significant effect on Antero Midstream's capital resources, liquidity and expected operating results. Natural gas and oil prices directly affect Antero Resources' production. If prices decrease further, it would reduce Antero Midstream's revenues and ability to pay distributions. Sustained reductions in development or production activity in Antero Midstream's areas of operation could lead to reduced utilization of Antero Midstream's services.

        Due to these and other factors, even if reserves are known to exist in areas served by Antero Midstream's assets, producers have chosen, and may choose in the future, not to develop those reserves. If reductions in development activity result in Antero Midstream's inability to maintain the current levels of throughput volumes on its systems, or its water services, or if reductions in lateral lengths result in a decrease in demand for Antero Midstream's water services on a per well basis, those reductions could reduce Antero Midstream's revenue and cash flow and adversely affect its ability to make cash distributions to its unitholders.

The gathering and compression agreement only includes minimum volume commitments under certain circumstances.

        The gathering and compression agreement includes minimum volume commitments only on high pressure pipelines and compressor stations that are constructed by Antero Midstream at Antero Resources' request after the Antero Midstream IPO. Antero Midstream's compressor stations and gathering pipelines existing prior to the Antero Midstream IPO are not supported by minimum volume commitments from Antero Resources. Any decrease in the current levels of throughput volumes on its gathering and compression systems could reduce its revenue and cash flow and adversely affect Antero Midstream's ability to make cash distributions to its unitholders.

Antero Midstream may not be able to attract third-party gathering and compression volumes or opportunities to provide water services, which could limit its ability to grow and maintain its dependence on Antero Resources.

        Part of Antero Midstream's long-term growth strategy includes diversifying its customer base by identifying opportunities to offer services to third parties. To date, substantially all of its revenues have been earned from Antero Resources. Antero Midstream's ability to increase throughput volumes on its gathering and compression systems and water services systems and any related revenue from third parties is subject to numerous factors beyond our control, including competition from third parties and the extent to which we have available capacity when requested by third parties. To the extent that Antero Midstream lacks available capacity on its systems for third-party volumes, Antero Midstream may not be able to compete effectively with third-party systems for additional oil and natural gas production in its areas of operation. In addition, some of its natural gas and NGLs marketing competitors for third-party volumes have greater financial resources and access to larger supplies of natural gas than those available to Antero Midstream, which could allow those competitors to price their services more aggressively than Antero Midstream does.

        Antero Midstream's efforts to attract new unaffiliated customers may be adversely affected by (i) its relationship with Antero Resources and the fact that a substantial majority of the capacity of Antero Midstream's gathering and compression systems and water systems will be necessary to service Antero Resources' production and development and completion schedule and (ii) its desire to provide services pursuant to fee-based contracts. As a result, Antero Midstream may not have the capacity to provide services to third parties and/or potential third-party customers may prefer to obtain services pursuant to other forms of contractual arrangements under which it would be required to assume direct commodity exposure.

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Antero Midstream will be required to make substantial capital expenditures to increase its asset base. If Antero Midstream is unable to obtain needed capital or financing on satisfactory terms, its ability to make cash distributions may be diminished or its financial leverage could increase.

        In order to increase Antero Midstream's asset base, it will need to make expansion capital expenditures. If it does not make sufficient or effective expansion capital expenditures, Antero Midstream will be unable to expand its business operations and, as a result, it will be unable to raise the level of its future cash distributions. To fund Antero Midstream's expansion capital expenditures and investment capital expenditures, it will be required to use cash from its operations or incur borrowings. Alternatively, Antero Midstream may sell additional common units or other securities to fund its capital expenditures. Such uses of cash from Antero Midstream's operations will reduce cash available for distribution to its unitholders. Antero Midstream's ability to obtain bank financing or its ability to access the capital markets for future equity or debt offerings may be limited by Antero Midstream's or Antero Resources' financial condition at the time of any such financing or offering and the covenants in its existing debt agreements, as well as by general economic conditions, contingencies and uncertainties that are beyond Antero Midstream's control. Even if it is successful in obtaining the necessary funds, the terms of such financings could limit Antero Midstream's ability to pay distributions to its unitholders. In addition, incurring additional debt may significantly increase Antero Midstream's interest expense and financial leverage, and issuing additional limited partner interests may result in significant unitholder dilution and would increase the aggregate amount of cash required to maintain the then current distribution rate, which could materially decrease Antero Midstream's ability to pay distributions at the prevailing distribution rate. Neither Antero Resources, AMP GP or any of their respective affiliates is committed to providing any direct or indirect support to fund Antero Midstream's growth.

Antero Midstream's gathering and compression and water handling and treatment systems are concentrated in the Appalachian Basin, making it vulnerable to risks associated with operating in one major geographic area.

        Antero Midstream relies primarily on revenues generated from gathering and compression and water handling and treatment systems that it owns, which are located in the Marcellus and Ohio Utica Shales. As a result of this concentration, Antero Midstream may be disproportionately exposed to the impact of regional supply and demand factors, delays or interruptions of production from wells in this area caused by governmental regulation, market limitations or interruption of the processing or transportation of natural gas, NGLs or oil.

The amount of cash Antero Midstream has available for distribution to its unitholders depends primarily on its cash flow and not solely on profitability, which may prevent Antero Midstream from making distributions, even during periods in which it records net income.

        You should be aware that the amount of cash Antero Midstream has available for distribution depends primarily upon Antero Midstream's cash flow and not solely on profitability, which will be affected by non-cash items. As a result, Antero Midstream may make cash distributions during periods when it records a net loss for financial accounting purposes, and conversely, Antero Midstream might fail to make cash distributions during periods when Antero Midstream records net income for financial accounting purposes.

Antero Midstream's construction or purchase of new gathering and compression, processing, water handling and treatment or other assets, including the water treatment facility currently under construction, may not be completed on schedule, at the budgeted cost or at all, and they may not result in revenue increases and may be subject to regulatory, environmental, political, legal and economic risks, which could adversely affect its cash flows, results of operations and financial condition and, as a result, Antero Midstream's ability to distribute cash to its unitholders.

        The construction of additions or modifications to Antero Midstream's existing systems and the construction or purchase of new assets, including the water treatment facility currently under construction,

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involves numerous regulatory, environmental, political and legal uncertainties beyond its control and may require the expenditure of significant amounts of capital. Financing may not be available on economically acceptable terms or at all. If Antero Midstream undertakes these projects, Antero Midstream may not be able to complete them on schedule, at the budgeted cost or at all. Moreover, Antero Midstream's revenues may not increase immediately upon the expenditure of funds on a particular project. For instance, the construction of the water treatment facility will occur over an extended period of time, and Antero Midstream will not receive any material increases in revenues until the project is completed. Moreover, Antero Midstream may construct facilities to capture anticipated future production growth in an area in which such growth does not materialize. As a result, new gathering and compression, processing, water handling and treatment or other assets may not be able to attract enough throughput volumes to achieve Antero Midstream's expected investment return, which could adversely affect its results of operations and financial condition. In addition, the construction of additions to Antero Midstream's existing assets may require it to obtain new rights-of-way prior to constructing new pipelines or facilities. Antero Midstream may be unable to timely obtain such rights-of-way to connect new natural gas supplies to its existing gathering pipelines or capitalize on other attractive expansion opportunities. Additionally, it may become more expensive for Antero Midstream to obtain new rights-of-way or to expand or renew existing rights-of-way. If the cost of renewing or obtaining new rights-of-way increases, its cash flows could be adversely affected.

If additional takeaway pipelines under construction or other pipeline projects are not completed, Antero Resources', and correspondingly Antero Midstream's, future growth may be limited.

        Antero Resources has secured sufficient long-term firm takeaway capacity on major pipelines that are in existence or currently under construction in each of its core operating areas to accommodate its current development plans; however, any failure of any pipeline under construction to be completed, or any unavailability of existing takeaway pipelines, could cause Antero Resources to curtail its future development and production plans. Sustained reductions in development or production activity in Antero Midstream's areas of operation could lead to reduced utilization of Antero Midstream's services, which could adversely affect Antero Midstream's operating margin, cash flow and ability to make cash distributions to its unitholders.

A shortage of equipment and skilled labor in the Appalachian Basin could reduce equipment availability and labor productivity and increase labor and equipment costs, which could have a material adverse effect on Antero Midstream's business and results of operations.

        Gathering and compression and water handling and treatment services require special equipment and laborers skilled in multiple disciplines, such as equipment operators, mechanics and engineers, among others. If Antero Midstream experiences shortages of necessary equipment or skilled labor in the future, its labor and equipment costs and overall productivity could be materially and adversely affected. If Antero Midstream's equipment or labor prices increase or if it experiences materially increased health and benefit costs for employees, Antero Midstream's results of operations could be materially and adversely affected.

If third-party pipelines or other midstream facilities interconnected to Antero Midstream's gathering and compression systems become partially or fully unavailable, its operating margin, cash flow and ability to make cash distributions to its unitholders could be adversely affected.

        Antero Midstream's gathering and compression assets connect to other pipelines or facilities owned and operated by unaffiliated third parties. The continuing operation of third-party pipelines, compressor stations and other midstream facilities is not within Antero Midstream's control. These pipelines, plants and other midstream facilities may become unavailable because of testing, turnarounds, line repair, maintenance, reduced operating pressure, lack of operating capacity, regulatory requirements and curtailments of receipt or deliveries due to insufficient capacity or because of damage from severe weather

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conditions or other operational issues. In addition, if the costs to Antero Midstream to access and transport on these third-party pipelines significantly increase, its profitability could be reduced. If any such increase in costs occurs or if any of these pipelines or other midstream facilities become unable to receive or transport natural gas, Antero Midstream's operating margin, cash flow and ability to make cash distributions to its unitholders could be adversely affected.

Antero Midstream's exposure to commodity price risk may change over time.

        Antero Midstream currently generates all of its revenues pursuant to fee-based contracts under which Antero Midstream is paid based on the volumes of natural gas and condensate that it gathers and compresses and water that it handles and treats, rather than the underlying value of the commodity. Consequently, Antero Midstream's existing operations and cash flows have little direct exposure to commodity price risk. Although Antero Midstream intends to enter into similar fee-based contracts with new customers in the future, Antero Resources Midstream's efforts to negotiate such contractual terms may not be successful. In addition, Antero Midstream may acquire or develop additional midstream assets in a manner that increases its exposure to commodity price risk. Future exposure to the volatility of natural gas, NGL and oil prices, especially in light of the recent declines, could have a material adverse effect on its business, results of operations and financial condition and, as a result, Antero Midstream's ability to make cash distributions to its unitholders.

Antero Midstream owns a 50% interest in the Joint Venture, which will be operated by MarkWest. While Antero Midstream has the ability to influence certain business decisions affecting the Joint Venture, the success of its investment in the Joint Venture will depend on MarkWest's operation of the Joint Venture.

        On February 6, 2017, Antero Midstream entered into the Joint Venture with MarkWest. While Antero Midstream and MarkWest each own a 50% interest in the Joint Venture, MarkWest is the primary operator of the Joint Venture. Accordingly, Antero Midstream will depend on MarkWest for the day-to-day operations of the Joint Venture. Antero Midstream's lack of control over the Joint Venture's day-to-day operations and the associated costs of operations could result in Antero Midstream receiving lower cash distributions from the Joint Venture than currently anticipated, which could reduce its cash available for distribution to its unitholders. In addition, differences in views among the owners of the Joint Venture could result in delayed decisions or in failures to agree on significant matters, potentially adversely affecting the business and results of operations or prospects of the Joint Venture and, in turn, the amount of cash from the Joint Venture operations distributed to Antero Midstream.

If the Joint Venture is not successful or if the Joint Venture does not perform as expected, Antero Midstream's future financial performance may be negatively impacted.

        Antero Midstream may be exposed to certain risks in connection with its ownership interest in the Joint Venture, including regulatory, environmental and litigation risks. If such risks or other anticipated or unanticipated liabilities were to materialize, any desired benefits of Antero Midstream's entry into the Joint Venture may not be fully realized, if at all, and its future financial performance may be negatively impacted.

        In addition, the Joint Venture may result in other difficulties including, among other things:

    diversion of Antero Midstream's management's attention from other business concerns;

    managing regulatory compliance and corporate governance matters;

    an increase in Antero Midstream's indebtedness; and

    potential environmental or other regulatory compliance matters or liabilities and/or title issues, including certain liabilities arising from the operation of the Joint Venture assets prior to the closing of the Joint Venture.

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Restrictions in Antero Midstream's revolving credit facility and its other debt agreements could adversely affect its business, financial condition, results of operations and ability to make quarterly cash distributions to its unitholders.

        Antero Midstream's revolving credit facility and the indenture governing its outstanding senior notes limit Antero Midstream's ability to, among other things:

    incur or guarantee additional debt;

    redeem or repurchase units or make distributions under certain circumstances;

    make certain investments and acquisitions;

    incur certain liens or permit them to exist;

    enter into certain types of transactions with affiliates;

    merge or consolidate with another company; and

    transfer, sell or otherwise dispose of assets.

        The indenture governing Antero Midstream's senior notes contains similar restrictive covenants. In addition, Antero Midstream's revolving credit facility and the indenture governing its outstanding senior notes also contain covenants requiring Antero Midstream to maintain certain financial ratios. Antero Midstream abilities to meet those financial ratios and tests can be affected by events beyond our control, and Antero Midstream cannot assure that it will meet any such ratios and tests. Additionally, Antero Midstream may not be able to borrow the full amount of commitments under its revolving credit facility if doing so would cause Antero Midstream to not meet a financial covenant.

        The provisions of Antero Midstream's revolving credit facility and the indenture governing its outstanding senior notes may affect its ability to obtain future financing and pursue attractive business opportunities and Antero Midstream's flexibility in planning for, and reacting to, changes in business conditions. In addition, a failure to comply with the provisions of Antero Midstream's revolving credit facility or the indenture governing its outstanding senior notes could result in a default or an event of default that could enable Antero Midstream's lenders or noteholders to declare the outstanding principal of debt outstanding under either arrangement, together with accrued and unpaid interest, to be immediately due and payable. If the payment of Antero Midstream's debt is accelerated, its assets may be insufficient to repay such debt in full, and Antero Midstream's unitholders could experience a partial or total loss of their investment. Please read "Management's Discussion and Analysis of Financial Condition and Results of Operations—Antero Midstream's Liquidity and Capital Resources."

If Antero Midstream's assets become subject to Federal Energy Regulatory Commission ("FERC") regulation or federal, state or local regulations or policies change, or if it fails to comply with market behavior rules, Antero Midstream's financial condition, results of operations and cash flows could be materially and adversely affected.

        Antero Midstream believes that its natural gas gathering and transportation operations are exempt from regulation by the FERC under the Natural Gas Act of 1938 (the "NGA"). Section 1(b) of the NGA exempts natural gas gathering facilities from regulation by the FERC under the NGA. Although the FERC has not made any formal determinations with respect to any of its facilities, Antero Midstream believes that the natural gas pipelines in its gathering systems meet the traditional tests the FERC has used to establish whether a pipeline is a gathering pipeline not subject to FERC jurisdiction. The distinction between FERC-regulated transmission services and federally unregulated gathering services, however, has been the subject of substantial litigation, and the FERC determines whether facilities are gathering facilities on a case-by-case basis, so the classification and regulation of our gathering facilities may be subject to change based on future determinations by the FERC, the courts, or Congress. If the FERC were to consider the status of an individual facility and determine that the facility or services provided by it are

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not exempt from FERC regulation under the NGA, the rates for, and terms and conditions of, services provided by such facility would be subject to regulation by the FERC under the NGA or the Natural Gas Policy Act of 1978 (the "NGPA"). Such regulation could decrease revenue, increase operating costs, and, depending upon the facility in question, could adversely affect Antero Midstream's results of operations and cash flows.

        Unlike natural gas gathering under the NGA, there is no exemption for the gathering of crude oil or NGLs under the Interstate Commerce Act, or ICA. Whether a crude oil or NGL shipment is in interstate commerce under the ICA depends on the fixed and persistent intent of the shipper as to the crude oil's or NGL's final destination, absent a break in the interstate movement. Antero Midstream believes that the crude oil and NGL pipelines in its gathering system meet the traditional tests the FERC has used to determine that a pipeline is not providing transportation service in interstate commerce subject to FERC ICA jurisdiction. However, the determination of the interstate or intrastate character of shipments on Antero Midstream's crude oil and NGL pipelines depends on the shipper's intentions and the transportation of the crude oil or NGLs outside of Antero Midstream's system, and may change over time. If the FERC were to consider the status of an individual facility and the character of a crude oil or NGL shipment, and determine that the shipment is in interstate commerce, the rates for, and terms and conditions of, transportation services provided by such facility would be subject to regulation by the FERC under the ICA. Such FERC regulation could decrease revenue, increase operating costs, and, depending on the facility in question, could adversely affect Antero Midstream's results of operations and cash flows. In addition, if any of Antero Midstream's facilities were found to have provided services or otherwise operated in violation of the ICA, this could result in the imposition of administrative and civil remedies and criminal penalties, as well as a requirement to disgorge charges collected for such services in excess of the rate established by the FERC.

        State regulation of gathering facilities and intrastate transportation pipelines generally includes various safety, environmental and, in some circumstances, non-discriminatory take and common purchaser requirements, as well as complaint-based rate regulation. Other state regulations may not directly apply to our business, but may nonetheless affect the availability of natural gas, crude oil and NGLs for purchase, compression and sale.

        Moreover, FERC regulations indirectly impact Antero Midstream's businesses and the markets for products derived from these businesses. The FERC's policies and practices across the range of its regulatory activities, including, for example, its policies on open access transportation, market manipulation, ratemaking, gas quality, capacity release and market center promotion, indirectly affect intrastate markets. Should Antero Midstream fail to comply with any applicable FERC administered statutes, rules, regulations and orders, Antero Midstream could be subject to substantial penalties and fines, which could have a material adverse effect on our results of operations and cash flows. The FERC has civil penalty authority under the NGA and NGPA to impose penalties for current violations of up to $1,193,970 per day for each violation and disgorgement of profits associated with any violation.

        For more information regarding federal and state regulation of Antero Midstream's operations, please read "Our Business—Regulation of Antero Midstream's Operations."

Antero Resources' ability to produce oil and gas economically and in commercial quantities is dependent on the availability of adequate supplies of water for drilling and completion operations and access to water and other waste disposal or recycling services at a reasonable cost and in accordance with applicable environmental rules. Restrictions on Antero's ability to obtain water or dispose of produced water and other waste may have an adverse effect on its financial condition, results of operations and cash flows.

        The hydraulic fracture stimulation process on which Antero Resources depends to produce commercial quantities of oil and gas requires the use and disposal of significant quantities of water. The availability of disposal alternatives to receive all of the water produced from Antero Resources' wells may

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affect Antero Resources' production. Antero Resources' inability to secure sufficient amounts of water, or to dispose of or recycle the water used in its operations, could adversely impact its operations. Antero Midstream owns two independent fresh water delivery systems that distribute fresh water to Antero Resources from the Ohio River and several regional water sources for well completion operations in the Marcellus and Ohio Utica Shales. Late in 2015, Antero Midstream began providing Antero Resources with wastewater services for our well completion operations, including wastewater transportation, disposal, and treatment.

        The inability to obtain water from Antero Resources' traditional sources of supply for any reason, including the loss of water rights, permit restrictions or drought, could adversely affect Antero Midstream's business and operating results. Additionally, the imposition of new environmental initiatives and regulations could include restrictions on Antero Resources' ability to obtain water or dispose of waste and adversely affect Antero Midstream's business and operating results.

Increased regulation of hydraulic fracturing could result in reductions or delays in natural gas, NGLs and oil production by Antero Midstream's customers, which could reduce the throughput volumes on its gathering and compression systems and the number of wells for which Antero Midstream provides water services, which could adversely impact its revenues.

        All of Antero Resources' natural gas, NGLs and oil production is being developed from unconventional sources, such as shale formations. These reservoirs require hydraulic fracturing completion processes to release the liquids and natural gas from the rock so it can flow through casing to the surface. Hydraulic fracturing is a well stimulation process that utilizes large volumes of water and sand (or other proppant) combined with fracturing chemical additives that are pumped at high pressure to crack open previously impenetrable rock to release hydrocarbons. Hydraulic fracturing is typically regulated by state oil and gas commissions and similar agencies. Some states, including those in which Antero Midstream operates, have adopted, and other states are considering adopting, regulations that could impose more stringent disclosure and/or well construction requirements on hydraulic fracturing operations. In December 2016, the U.S. Environmental Protection Agency ("EPA") released its final report on the potential impacts of hydraulic fracturing on drinking water resources. The final report concluded that "water cycle" activities associated with hydraulic fracturing may impact drinking water resources "under some circumstances," noting that the following hydraulic fracturing water cycle activities and local- or regional-scale factors are more likely than others to result in more frequent or more severe impacts: water withdrawals for fracturing in times or areas of low water availability; surface spills during the management of fracturing fluids, chemicals or produced water; injection of fracturing fluids into wells with inadequate mechanical integrity; injection of fracturing fluids directly into groundwater resources; discharge of inadequately treated fracturing wastewater to surface waters; and disposal or storage of fracturing wastewater in unlined pits. Since the report did not find a direct link between hydraulic fracturing itself and contamination of groundwater resources, this years-long study does not appear to provide any basis for further regulation of hydraulic fracturing at the federal level.

        Antero Midstream cannot predict whether any such legislation will ever be enacted and if so, what its provisions would be. If additional levels of regulation and permits were required through the adoption of new laws and regulations at the federal or state level, that could lead to delays, increased operating costs and process prohibitions that could reduce the volumes of liquids and natural gas that move through our gathering systems or reduce the number of wells drilled and completed that require fresh water for hydraulic fracturing activities, which in turn could materially adversely affect our revenues and results of operations.

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Certain U.S. federal income tax deductions currently available with respect to crude oil and natural gas exploration and development may be eliminated as a result of future legislation, which could result in reductions or delays in natural gas, NGLs and oil production by Antero Midstream's customers, which could reduce the throughput volumes on its gathering and compression systems and the number of wells for which Antero Midstream provides water services, which could adversely impact its revenues.

        Antero Resources is subject to changing and extensive tax laws, the effects of which cannot be predicted. In past years, legislation has been proposed in the Congress that, if enacted into law, would make significant changes to U.S. tax laws, including, but not limited to, the elimination of certain key U.S. federal income tax incentives currently available to crude oil and natural gas exploration and production companies. These changes have included, but are not limited to, (i) the repeal of the percentage depletion allowance for oil and gas properties, (ii) the elimination of current deductions for intangible drilling and development costs, (iii) the elimination of the deduction for certain domestic production activities and (iv) an extension of the amortization period for certain geological and geophysical expenditures. Congress could consider, and could include, some or all of these proposals as part of tax reform legislation. Moreover, other more general features of tax reform legislation, including changes to cost recovery rules and to the deductibility of interest expense, may be developed that also would change the taxation of crude oil and natural gas exploration and production companies. It is unclear whether these or similar changes will be enacted and, if enacted, how soon any such changes could take effect. The passage of any legislation as a result of these proposals or any similar changes in U.S. federal income tax laws could defer or eliminate certain tax deductions that are currently available to Antero Resources with respect to its crude oil and natural gas exploration and development, and any such change could materially and adversely affect its business and financial condition.

Antero Midstream or its customers may incur significant liability under, or costs and expenditures to comply with, environmental and worker health and safety regulations, which are complex and subject to frequent change.

        As an owner, lessee or operator of gathering pipelines and compressor stations, Antero Midstream is subject to various stringent federal, state, provincial and local laws and regulations relating to the discharge of materials into, and protection of, the environment. Numerous governmental authorities, such as the EPA and analogous state agencies, have the power to enforce compliance with these laws and regulations and the permits issued under them, oftentimes requiring difficult and costly response actions. These laws and regulations may impose various obligations that are applicable to Antero Midstream and its customers' operations, including the acquisition of permits to conduct regulated activities, the incurrence of capital or operating expenditures to limit or prevent releases of materials from Antero Midstream or its customers' operations, the imposition of specific standards addressing worker protection, and the imposition of substantial liabilities and remedial obligations for pollution or contamination resulting from Antero Midstream or its customers' operations. Failure to comply with these laws, regulations and permits may result in joint and several, strict liability and the assessment of administrative, civil and criminal penalties, the imposition of remedial obligations, and the issuance of injunctions limiting or preventing some or all of our operations. Private parties, including the owners of the properties through which Antero Midstream's gathering systems pass and facilities where wastes resulting from Antero Midstream's operations are taken for reclamation or disposal, may also have the right to pursue legal actions to enforce compliance, as well as to seek damages for non-compliance, with environmental laws and regulations or for personal injury or property damage. Antero Midstream may not be able to recover all or any of these costs from insurance. In addition, Antero Midstream may experience a delay in obtaining or be unable to obtain required permits, which may cause it to lose potential and current customers, interrupt its operations and limit growth and revenues, which in turn could affect our profitability. There is no assurance that changes in or additions to public policy regarding the protection of the environment will not have a significant impact on Antero Midstream's operations and profitability.

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        Antero Midstream's operations also pose risks of environmental liability due to leakage, migration, releases or spills from Antero Midstream's operations to surface or subsurface soils, surface water or groundwater. Certain environmental laws impose strict as well as joint and several liability for costs required to remediate and restore sites where hazardous substances, hydrocarbons, or solid wastes have been stored or released. Antero Midstream may be required to remediate contaminated properties currently or formerly operated by Antero Midstream or facilities of third parties that received waste generated by Antero Midstream's operations regardless of whether such contamination resulted from the conduct of others or from consequences of Antero Midstream's actions that were in compliance with all applicable laws at the time those actions were taken. In addition, claims for damages to persons or property, including natural resources, may result from the environmental, health and safety impacts of our operations. Moreover, public interest in the protection of the environment has increased dramatically in recent years, and additional regulation of the oil and natural gas sector is likely. For example, in June 2016, the EPA finalized rules under the federal Clean Air Act regarding criteria for aggregating multiple sites into a single source for air-quality permitting purposes applicable to the oil and gas industry. This rule could cause small facilities (such as tank batteries and compressor stations), on an aggregate basis, to be deemed a major source, thereby triggering more stringent air permitting requirements, which in turn could result in operational delays or require such facilities to install costly pollution control equipment. The trend of more expansive and stringent environmental legislation and regulations applied to the crude oil and natural gas industry could continue, resulting in increased costs of doing business and consequently affecting profitability. Please read "Our Business—Regulation of Environmental and Occupational Safety and Health Matters" for more information.

Climate change laws and regulations restricting emissions of "greenhouse gases" ("GHG") could result in increased operating costs and reduced demand for the natural gas that Antero Midstream gathers while potential physical effects of climate change could disrupt its production and cause Antero Midstream to incur significant costs in preparing for or responding to those effects.

        The EPA has determined that emissions of GHGs present an endangerment to public health and the environment because emissions of such gases are, according to the EPA, contributing to the warming of the earth's atmosphere and other climatic changes. Based on these findings, EPA has adopted regulations under existing provisions of the federal Clean Air Act, that establish Prevention of Significant Deterioration, or PSD, preconstruction permits, and Title V operating permits for GHG emissions from certain large stationary sources. Under these regulations, facilities required to obtain PSD permits must meet BACT standards for their GHG emissions established by the states or, in some cases, by the EPA, on a case-by-case basis. The EPA has also adopted rules requiring the monitoring and reporting of GHG emissions from specified sources in the United States, including, among others, certain onshore oil and natural gas processing and fractionating facilities. More recently, in June 2016, the EPA finalized new regulations that set emissions standards for methane and volatile organic compounds from new and modified oil and natural gas production and natural gas processing and transmission facilities as part of the Obama Administration's efforts to reduce methane emissions from the oil and natural gas sector by up to 45% from 2012 levels by 2025. The EPA has also announced (but has not yet proposed) methane emission standards for existing sources in addition to new sources. These rules (and any additional regulations) could impose new compliance costs and permitting burdens on natural gas and midstream operations. In addition, the United States (along with numerous other nations) agreed to the Paris Agreement on climate change in December 2015, which agreement entered into force in November 2016. Additionally, while Congress has from time to time considered legislation to reduce emissions of GHGs, the prospect for adoption of significant legislation at the federal level to reduce GHG emissions is perceived to be low at this time. Although it is not possible at this time to predict how any new legislation or regulations (including any such matters relating to the Paris Agreement) that may be adopted to address GHG emissions would impact Antero Midstream's business, any such future laws and regulations that limit emissions of GHGs could adversely affect demand for the oil and natural gas that exploration and

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production operators produce, some of whom are Antero Midstream's customers, which could thereby reduce demand for Antero Midstream's services. Finally, it should be noted that some scientists have concluded that increasing concentrations of GHGs in the Earth's atmosphere may produce climate changes that have significant physical effects, such as increased frequency and severity of storms, droughts and floods and other climatic events; if any such effects were to occur, it is uncertain if they would have an adverse effect on Antero Midstream's financial condition and operations.

Antero Midstream may incur significant costs and liabilities as a result of pipeline integrity management program testing and any related pipeline repair or preventative or remedial measures.

        The United States Department of Transportation, or DOT, through the Pipeline and Hazardous Materials Safety Administration, or PHMSA, has adopted regulations requiring pipeline operators to develop integrity management programs for transportation pipelines located where a leak or rupture could do the most harm, in "high consequence areas." The regulations require operators to:

    perform ongoing assessments of pipeline integrity;

    identify and characterize applicable threats to pipeline segments that could impact a high consequence area;

    improve data collection, integration and analysis;

    repair and remediate the pipeline as necessary; and

    implement preventive and mitigating actions.

        The Pipeline Safety, Regulatory Certainty and Job Creation Act of 2011, or the 2011 Pipeline Safety Act, among other things, increased the maximum civil penalty for pipeline safety violations and directed the Secretary of Transportation to promulgate rules or standards relating to expanded integrity management requirements, automatic or remote-controlled valve use, excess flow valve use, leak detection system installation and testing to confirm the material strength of pipe operating above 30% of specified minimum yield strength in high consequence areas. Consistent with the 2011 Pipeline Safety Act, PHMSA finalized rules that increased the maximum administrative civil penalties for violations of the pipeline safety laws and regulations to $200,000 per violation per day, with a maximum of $2,000,000 for a related series of violations. Effective August 1, 2016, those maximum civil penalties were increased to $205,638 per violation per day, with a maximum of $2,056,380 for a series of violations, to account for inflation. Additionally, in May 2011, PHMSA published a final rule adding reporting obligations and integrity management standards to certain rural low-stress hazardous liquid pipelines that were not previously regulated in such manner. Should Antero Midstream fail to comply with DOT, PHMSA or comparable state regulations, Antero Midstream could be subject to substantial penalties and fines, which could impact our results of operations.

        On June 22, 2016, President Obama signed into law new legislation entitled Protecting our Infrastructure of Pipelines and Enhancing Safety Act of 2016, or the PIPES Act. The PIPES Act reauthorizes PHMSA through 2019, and facilitates greater pipeline safety by providing PHMSA with emergency order authority, including authority to issue prohibitions and safety measures on owners and operators of gas or hazardous liquid pipeline facilities to address imminent hazards, without prior notice or an opportunity for a hearing, as well as enhanced release reporting requirements, requiring a review of both natural gas and hazardous liquid integrity management programs, and mandating the creation of a working group to consider the development of an information-sharing system related to integrity risk analyses. The PIPES Act also requires that PHMSA publish periodic updates on the status of those mandates outstanding from the 2011 Pipeline Safety Act, of which approximately half remain to be completed. The mandates yet to be acted upon include requiring certain shut-off valves on transmission lines, mapping all high consequence areas, and shortening the deadline for accident and incident notifications.

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        PHMSA regularly revises its pipeline safety regulations. For example, in March 2015, PHMSA finalized new rules applicable to gas and hazardous liquid pipelines that, among other changes, impose new post-construction inspections, welding, gas component pressure testing requirements, as well as requirements for calculating pressure reductions for immediate repairs on liquid pipelines. In addition, in May 2016, PHMSA proposed rules that would, if adopted, impose more stringent requirements for certain gas lines. Among other things, the proposed rulemaking would extend certain of PHMSA's current regulatory safety programs for gas pipelines beyond "high consequence areas" to cover gas pipelines found in newly-defined "moderate consequence areas" that contain as few as five dwellings within the potential impact area and would also require gas pipelines installed before 1970 that are currently exempted from certain pressure testing obligations to be tested to determine their maximum allowable operating pressures ("MAOP"). Other new requirements proposed by PHMSA under the rulemaking would require pipeline operators to: report to PHMSA in the event of certain MAOP exceedances; strengthen PHMSA integrity management requirements; consider seismicity in evaluating threats to a pipeline; conduct hydrostatic testing for all pipeline segments manufactured using longitudinal seam welds; and use more detailed guidance from PHMSA in the selection of assessment methods to inspect pipelines. The proposed rulemaking also seeks to impose a number of requirements on gas gathering lines. More recently, in January 2017, PHMSA finalized regulations for hazardous liquid pipelines that significantly extend and expand the reach of certain PHMSA integrity management requirements (i.e., periodic assessments, leak detection and repairs), regardless of the pipeline's proximity to a high consequence area. The final rule also imposes new reporting requirements for certain unregulated pipelines, including all hazardous liquid gathering lines. The adoption of these and other laws or regulations that apply more comprehensive or stringent safety standards could require Antero Midstream to install new or modified safety controls, pursue new capital projects, or conduct maintenance programs on an accelerated basis, all of which could require Antero Midstream to incur increased operational costs that could be significant. While we cannot predict the outcome of legislative or regulatory initiatives, such legislative and regulatory changes could have a material effect on Antero Midstream's and our cash flow. Please read "Our Business—Regulation of Antero Midstream's Operations—Pipeline Safety Regulation" for more information.

Antero Midstream's business involves many hazards and operational risks, some of which may not be fully covered by insurance. The occurrence of a significant accident or other event that is not fully insured could curtail its operations and have a material adverse effect on Antero Midstream's ability to distribute cash and, accordingly, the market price for its common units.

        Antero Midstream's operations are subject to all of the hazards inherent in the gathering and compression of natural gas, including:

    unintended breach of impoundment and downstream flooding, release of invasive species or aquatic pathogens, hazardous spills near intake points, trucking collision, vandalism, excessive road damage or bridge collapse and unauthorized access or use of automation controls;

    damage to pipelines, compressor stations, pump stations, impoundments, related equipment and surrounding properties caused by natural disasters, acts of terrorism and acts of third parties;

    damage from construction, farm and utility equipment as well as other subsurface activity (for example, mine subsidence);

    leaks of natural gas, NGLs or oil or losses of natural gas, NGLs or oil as a result of the malfunction of equipment or facilities;

    fires, ruptures and explosions;

    other hazards that could also result in personal injury and loss of life, pollution and suspension of operations; and

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    hazards experienced by other operators that may affect our operations by instigating increased regulations and oversight.

        Any of these risks could adversely affect Antero Midstream's ability to conduct operations or result in substantial loss to it as a result of claims for:

    injury or loss of life;

    damage to and destruction of property, natural resources and equipment;

    pollution and other environmental damage;

    regulatory investigations and penalties;

    suspension of its operations; and

    repair and remediation costs.

        Antero Midstream may elect not to obtain insurance for any or all of these risks if Antero Midstream believes that the cost of available insurance is excessive relative to the risks presented. In addition, pollution and environmental risks generally are not fully insurable under policies we are covered under, and neither Antero Midstream nor AMP GP on its behalf have obtained pollution insurance. The occurrence of an event that is not fully covered by insurance could have a material adverse effect on Antero Midstream's business, financial condition and results of operations.

Antero Midstream does not own all of the land on which its pipelines and facilities are located, which could result in disruptions to its operations.

        Antero Midstream does not own all of the land on which its pipelines and facilities have been constructed, and Antero Midstream is, therefore, subject to the possibility of more onerous terms or increased costs to retain necessary land use if Antero Midstream does not have valid rights-of-way or if such rights-of-way lapse or terminate. Antero Midstream obtains the rights to construct and operate its pipelines on land owned by third parties and governmental agencies for a specific period of time. Antero Midstream's loss of these rights, through its inability to renew right-of-way contracts or otherwise, could have a material adverse effect on its business, results of operations, financial condition and ability to make cash distributions to its unitholders.

Antero Midstream is subject to complex federal, state and local laws and regulations that could adversely affect the cost, manner or feasibility of conducting its operations or expose it to significant liabilities.

        Antero Midstream's operations are subject to complex and stringent federal, state and local laws and regulations. In order to conduct Antero Midstream's operations in compliance with these laws and regulations, Antero Midstream must obtain and maintain numerous permits, approvals and certificates from various federal, state and local governmental authorities. Antero Midstream may incur substantial costs in order to maintain compliance with these existing laws and regulations and the permits and other approvals issued thereunder. In addition, Antero Midstream's costs of compliance may increase or operational delays may occur if existing laws and regulations are revised or reinterpreted, or if new laws and regulations apply to its operations. Failure to comply with such laws and regulations, including any evolving interpretation and enforcement by governmental authorities, could have a material adverse effect on Antero Midstream's business, financial condition and results of operations. Also, Antero Midstream might not be able to obtain or maintain all required environmental or regulatory approvals for its operations. If there is a delay in obtaining any required environmental or regulatory approvals, or if Antero Midstream fails to obtain and comply with them, the operation or construction of its facilities could be prevented or become subject to additional costs.

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        In addition, new or additional regulations or permitting requirements, new interpretations of existing requirements or changes in Antero Midstream's operations could also trigger the need for Environmental Assessments or more detailed Environmental Impact Statements under the National Environmental Policy Act and analogous state laws, as well as litigation over the adequacy of those reviews, which could result in increased costs or delays of, or denial of rights to conduct, Antero Midstream's development programs. Such potential regulations or litigation could increase our operating costs, reduce Antero Midstream's liquidity, delay or halt its operations or otherwise alter the way it conducts its business, which could in turn have a material adverse effect on Antero Midstream's business, financial condition and results of operations. Further, the discharges of oil, natural gas, NGLs and other pollutants into the air, soil or water may give rise to significant liabilities on Antero Midstream's part to the government and third parties. Please read "Our Business—Regulation of Environmental and Occupational Safety and Health Matters" for a further description of laws and regulations that affect Antero Midstream.

The loss of key personnel could adversely affect Antero Midstream's ability to operate.

        Antero Midstream depends on the services of a relatively small group of its general partner's senior management and technical personnel. Antero Midstream does not maintain, nor does it plan to obtain, any insurance against the loss of any of these individuals. The loss of the services of its general partner's senior management or technical personnel, including Paul M. Rady, Chairman and Chief Executive Officer, and Glen C. Warren, Jr., President, could have a material adverse effect on Antero Midstream's business, financial condition and results of operations.

Antero Midstream does not have any officers or employees and rely solely on officers of its general partner and employees of Antero Resources.

        Antero Midstream is managed and operated by the board of directors of AMP GP. Affiliates of Antero Resources conduct businesses and activities of their own in which Antero Midstream has no economic interest. As a result, there could be material competition for the time and effort of the officers and employees who provide services to our general partner and Antero Resources. If AMP GP and the officers and employees of Antero Resources do not devote sufficient attention to the management and operation of its business, its financial results may suffer, and Antero Midstream's ability to make distributions to its unitholders may be reduced.

Debt Antero Midstream incurs in the future may limit its flexibility to obtain financing and to pursue other business opportunities.

        Antero Midstream's future level of debt could have important consequences to it, including the following:

    Antero Midstream's ability to obtain additional financing, if necessary, for working capital, capital expenditures (including required drilling pad connections and well connections pursuant to its gathering and compression agreements as well as acquisitions) or other purposes may be impaired or such financing may not be available on favorable terms;

    Antero Midstream's funds available for operations, future business opportunities and distributions to its unitholders will be reduced by that portion of Antero Midstream's cash flow required to make interest payments on its debt;

    Antero Midstream may be more vulnerable to competitive pressures or a downturn in its business or the economy generally; and

    Antero Midstream's flexibility in responding to changing business and economic conditions may be limited.

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        Antero Midstream's ability to service its debt will depend upon, among other things, its future financial and operating performance, which will be affected by prevailing economic conditions and financial, business, regulatory and other factors, some of which are beyond Antero Midstream's control. If Antero Midstream's operating results are not sufficient to service any future indebtedness, Antero Midstream will be forced to take actions such as reducing distributions, reducing or delaying Antero Midstream's business activities, investments or capital expenditures, selling assets or issuing equity. Antero Midstream may not be able to effect any of these actions on satisfactory terms or at all.

If Antero Midstream ceases to be eligible to utilize its at-the-market equity offering program, its financial flexibility and liquidity could be adversely affected.

        Antero Midstream has historically used sales of common units under its at-the-market equity offering program to partially fund capital expenditures. As of December 31, 2016, Antero Midstream had approximately $185 million of available capacity under its at-the-market equity offering program. If Antero Midstream ceases to be eligible to utilize its at-the-market equity offering program, it may be required to find alternate sources to fund capital expenditures, which could reduce its financial flexibility and adversely affect its liquidity.

Terrorist attacks or cyber-attacks could have a material adverse effect on Antero Midstream's business, financial condition or results of operations.

        Terrorist attacks or cyber-attacks may significantly affect the energy industry, including Antero Midstream's operations and those of its customers, as well as general economic conditions, consumer confidence and spending and market liquidity. Strategic targets, such as energy-related assets, may be at greater risk of future attacks than other targets in the United States. Antero Midstream's insurance may not protect it against such occurrences. Consequently, it is possible that any of these occurrences, or a combination of them, could have a material adverse effect on its business, financial condition and results of operations.

Tax Risks

        As our only cash-generating assets at the closing of this offering will consist of our capital interest in IDR LLC and its related direct interests in Antero Midstream, our tax risks are primarily derivative of the tax risks associated with an investment in Antero Midstream.

The tax treatment of Antero Midstream depends on its status as a partnership for U.S. federal income tax purposes, as well as it not being subject to a material amount of entity-level taxation by individual states. If the Internal Revenue Service ("IRS") were to treat Antero Midstream as a corporation or Antero Midstream becomes subject to additional amounts of entity-level taxation for state or foreign tax purposes, it would reduce the amount of cash available for distribution to us.

        Upon the completion of this offering, we will continue to own all of the capital interests in IDR LLC, which directly owns all of the IDRs. Accordingly, the value of our investment in IDR LLC, as well as the anticipated after-tax economic benefit of an investment in our common shares, depends largely on Antero Midstream being treated as a partnership for U.S. federal income tax purposes, which requires that 90% or more of Antero Midstream's gross income for every taxable year consist of qualifying income, as defined in Section 7704 of the Internal Revenue Code of 1986, as amended (the "Code").

        Despite the fact that Antero Midstream is a limited partnership under Delaware law and, unlike us, has not elected to be treated as a corporation for U.S. federal income tax purposes, it is possible, under certain circumstances, for Antero Midstream to be treated as a corporation for U.S. federal income tax purposes. Although we do not believe, based on its current operations, that Antero Midstream will be so treated, a change in Antero Midstream's business could cause it to be treated as a corporation for U.S.

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federal income tax purposes or otherwise subject it to U.S. federal income taxation as an entity. Current law may change, causing Antero Midstream to be treated as a corporation for U.S. federal income tax purposes or otherwise subjecting Antero Midstream to entity-level taxation. In addition, several states are evaluating ways to subject partnerships to entity-level taxation through the imposition of state income, franchise and other forms of taxation.

        If Antero Midstream were treated as a corporation for U.S. federal income tax purposes, it would pay federal income tax on its taxable income at the corporate tax rate, which is currently a maximum of 35%, and would likely pay state income taxes at varying rates. Distributions to Antero Midstream's partners, including IDR LLC, would generally be taxed again as corporate distributions, and no income, gains, losses or deductions would flow through to Antero Midstream's partners. Because a tax would be imposed upon Antero Midstream as a corporation, its cash available for distribution would be substantially reduced. Therefore, treatment of Antero Midstream as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to us, likely causing a substantial reduction in the value of our common shares.

        Antero Midstream's partnership agreement provides that if a law is enacted or existing law is modified or interpreted in a manner that subjects Antero Midstream to taxation as a corporation or otherwise subjects Antero Midstream to entity-level taxation for U.S. federal income, state or local tax purposes, Antero Midstream's minimum quarterly distribution and target distribution amounts will be adjusted to reflect the impact of that law on Antero Midstream. If this were to happen, the amount of distributions IDR LLC receives from Antero Midstream and our resulting cash flows could be reduced substantially, which would adversely affect our ability to pay distributions.

The tax treatment of publicly traded partnerships such as Antero Midstream could be subject to potential legislative, judicial or administrative changes and differing interpretations, possibly on a retroactive basis.

        The present U.S. federal income tax treatment of publicly traded partnerships, including Antero Midstream, may be modified by administrative, legislative or judicial changes, or differing interpretations at any time. Any modifications to the U.S. federal income tax laws that may be applied retroactively or prospectively could make it more difficult or impossible to meet the expectation of future cash distributions or reduce the cash available for distributions to our shareholders. For example, from time to time, members of Congress propose and consider substantive changes to the existing federal income tax laws that affect publicly traded partnerships.

        In addition, the Internal Revenue Service, on May 5, 2015, issued proposed regulations concerning which activities give rise to qualifying income within the meaning of Section 7704 of the Internal Revenue Code. We do not believe the proposed regulations affect Antero Midstream's ability to qualify as a publicly traded partnership. However, finalized regulations could modify the amount of Antero Midstream's gross income that it is able to treat as qualifying income for the purposes of the qualifying income requirement.

        Antero Midstream is unable to predict whether any of these changes or other proposals will be reintroduced or ultimately will be enacted. Any such changes could negatively impact the value of our indirect investment in Antero Midstream. Any modification to the U.S. federal income tax laws may be applied retroactively and could make it more difficult or impossible to meet the exception for certain publicly traded partnerships to be treated as partnerships for U.S. federal income tax purposes.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

        Some of the information in this prospectus may contain forward-looking statements. Forward-looking statements give our current expectations, contain projections of results of operations or of financial condition, or forecasts of future events. Words such as "may," "assume," "forecast," "position," "predict," "strategy," "expect," "intend," "plan," "estimate," "anticipate," "believe," "project," "budget," "potential," or "continue," and similar expressions are used to identify forward-looking statements. They can be affected by assumptions used or by known or unknown risks or uncertainties. Consequently, no forward-looking statements can be guaranteed. When considering these forward-looking statements, you should keep in mind the risk factors and other cautionary statements in this prospectus. Actual results may vary materially. You are cautioned not to place undue reliance on any forward-looking statements. You should also understand that it is not possible to predict or identify all such factors and should not consider the following list to be a complete statement of all potential risks and uncertainties. Factors that could cause our actual results to differ materially from the results contemplated by such forward-looking statements include:

    our ability to pay distributions to our common shareholders;

    our expected receipt of, and the amounts of, distributions from Antero Midstream and IDR LLC in respect of the IDRs;

    Antero Resources' inability to meet its drilling and development plan;

    our and Antero Midstream's business strategy;

    realized natural gas, NGLs and oil prices;

    competition and government regulations;

    actions taken by third-party producers, operators, processors and transporters;

    pending legal or environmental matters;

    costs of conducting our gathering and compression operations;

    general economic conditions;

    credit markets;

    operating hazards, natural disasters, weather-related delays, casualty losses and other matters beyond our control;

    uncertainty regarding our and Antero Midstream's future operating results; and

    plans, objectives, expectations and intentions contained in this prospectus that are not historical.

        We caution you that these forward-looking statements are subject to all of the risks and uncertainties, most of which are difficult to predict and many of which are beyond our and Antero Midstream's control, incident to the gathering and compression business. These risks include, but are not limited to, commodity price volatility, inflation, environmental risks, drilling and completion and other operating risks, regulatory changes, the uncertainty inherent in projecting future rates of production, cash flow and access to capital, the timing of development expenditures, and the other risks described under "Risk Factors" in this prospectus.

        Should one or more of the risks or uncertainties described in this prospectus occur, or should underlying assumptions prove incorrect, our and Antero Midstream's actual results and plans could differ materially from those expressed in any forward-looking statements.

        All forward-looking statements, expressed or implied, included in this prospectus are expressly qualified in their entirety by this cautionary statement. This cautionary statement should also be

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considered in connection with any subsequent written or oral forward-looking statements that we or persons acting on our behalf may issue.

        Except as otherwise required by applicable law, we disclaim any duty to update any forward-looking statements, all of which are expressly qualified by the statements in this section, to reflect events or circumstances after the date of this prospectus.

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ORGANIZATIONAL STRUCTURE

        The diagram below depicts our organizational structure immediately following the completion of this offering (assuming the underwriters' option to purchase additional common shares is not exercised):

GRAPHIC


(1)
Series B Units represents the right to receive up to 6% of the aggregate distributions paid by IDR LLC in excess of $7.5 million. Each Series B Holder will also have the right to redeem all or a portion of its vested Series B Units in exchange for newly-issued common shares in us with a value equal to its pro rata share of up to 6% of any increase in our equity value (calculated by reference to the 20-day volume weighted average price of our common shares preceding the date of the redemption request) in excess of $2.0 billion.

(2)
We own all of the capital interests in IDR LLC, which owns all of the IDRs in Antero Midstream. Following the completion of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on its IDRs.

Reorganization

        Effective December 31, 2016, ARMM, our Predecessor, contributed the IDRs to IDR LLC in exchange for 2,000,000 Series A Units. Following such contribution, 80,000 Series B Units were issued to the Series B Holders in December 2016 and 20,000 Series B Units were issued to the Series B Holders in January 2017. In connection with the completion of this offering, the following transactions will be effected, which will result in the revised organizational structure depicted above under "Organizational Structure":

    the Sponsors will form AMGP GP, which will be admitted as the managing member of ARMM with a non-economic general partner interest in ARMM;

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    ARMM will convey its non-economic general partner interest in Antero Midstream to AMP GP, ARMM's wholly owned subsidiary, as a capital contribution;

    (i) ARMM will be converted under Delaware law to a Delaware limited partnership, and in connection with such conversion, will change its name to Antero Midstream GP LP, (ii) AMGP GP's managing member interest in ARMM will be converted to a non-economic general partner interest in us, and (iii) the remaining membership interest in ARMM will be converted into our common shares;

    The selling shareholder will sell            common shares to the public for net proceeds of approximately $            ;

    Antero Investment will liquidate and distribute the cash received in the prior step, along with its remaining common shares to the ARI Members on a pro rata basis; and

    The selling shareholder will sell up to            common shares to the public in connection with the exercise by the underwriters of their option to purchase additional common shares for net proceeds of approximately $            .

        We refer to the transactions described above collectively as the "Reorganization." Upon the completion of the Reorganization, our sole assets will consist of our interest in the general partner of Antero Midstream and all of the capital interests in IDR LLC. Although we will convert to a limited partnership in connection with the Reorganization, we will elect to be taxed as a corporation for U.S. federal income tax purposes.

Series B Units and Redemption Right

        IDR LLC has two classes of membership interests: (i) capital interests referred to as Series A Units and (ii) profits interests referred to as Series B Units. Following the completion of this offering, we will continue to own all of the Series A Units and the Series B Holders will continue to own all of the Series B Units.

        The Series B Holders will receive an aggregate distribution of up to 6% of all quarterly cash distributions in excess of $7.5 million distributed by Antero Midstream on the IDRs and we will receive all remaining distributions. The Series B Units are subject to restrictions on transfer and vest over three years in one-third increments upon each anniversary of the vesting commencement date. As Series B Units vest, each holder of such vested Series B Units will be entitled to receive a make-whole distribution corresponding to the aggregate amount of distributions such holder would have received on such Series B Units had they vested on the vesting commencement date. In anticipation of such make-whole distributions, each quarter we expect to retain from the cash distributions we receive on the Series A Units an amount corresponding to the aggregate amount of all make-whole distributions for such quarter.

        Each Series B Holder will also have the right to redeem all or a portion of its vested Series B Units in exchange for newly-issued common shares in us with a value equal to its pro rata share of up to 6% of any increase in our equity value (calculated by reference to the 20-day volume weighted average price of our common shares preceding the date of the redemption request) in excess of $2.0 billion. We refer to this right as the Redemption Right. In no event will the aggregate number of newly-issued common shares issued pursuant to the Redemption Right exceed 6% of the total number of our issued and outstanding common shares. Upon the exercise of the Redemption Right, the redeeming member will surrender its Series B Units to IDR LLC for cancellation. The limited liability company agreement of IDR LLC requires that we contribute a number of common shares to IDR LLC sufficient to satisfy the Redemption Right. IDR LLC will then transfer those common shares to such Series B Holder to complete the redemption. In the event a Series B Holder exercises its Redemption Right with respect to its vested Series B Units, we may, at our option, effect a direct exchange of our common shares for such vested Series B Units in lieu of a redemption of such vested Series B Units by IDR LLC. On or after

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December 31, 2026, we will have the right to cause each outstanding Series B Unit to be redeemed for common shares in us in accordance with the IDR LLC Agreement.

        For additional information, please read "Certain Relationships and Related Party Transactions—Limited Liability Company Agreement of IDR LLC."

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USE OF PROCEEDS

        All of the common shares being sold in this offering are being offered by the selling shareholder, and we will not receive any of the net proceeds from the sale of common shares in this offering, including in connection with the underwriters' option to purchase additional common shares. We expect that the total expenses of this offering, excluding underwriting discounts and commissions, will be approximately $             million. We will pay the expenses of the offering.

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CAPITALIZATION

        The following table sets forth the consolidated historical capitalization as of December 31, 2016:

    on an actual basis for our Predecessor; and

    on an as adjusted basis to give effect to the Reorganization described under "Organizational Structure" that will occur simultaneously with the closing of this offering.

        The historical financial data of our Predecessor presented in the table below is derived from and should be read in conjunction with the historical financial statements, including the accompanying notes, included elsewhere in this prospectus. There have been no material changes to the capitalization of our Predecessor since December 31, 2016.

 
  As of December 31,
2016
 
 
  Actual   Pro Forma  
 
  (in thousands)
 

Cash

  $ 9,609   $         

Total members' equity:

             

Total members' equity

    10,269               

Common shares

                

Total capitalization

  $ 10,269   $         

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DILUTION

        Dilution is the amount by which the offering price paid by the purchasers of common shares sold in this offering will exceed the pro forma net tangible book value per common share after the offering. On a pro forma basis as of December 31, 2016, after giving effect to the offering of common shares at an initial public offering price of $            per common share, the net tangible book value of our assets would have been $             million, or $            per common share. The net tangible book value remains unchanged when adjusted for the sale of common shares in this offering by the selling shareholder and regardless of whether the underwriters' option to purchase additional shares is exercised. Purchasers of common shares in this offering will experience substantial and immediate dilution in net tangible book value per common share for financial accounting purposes, as illustrated in the following table:

 
  Common
Shares Acquired
  Total
Consideration
   
 
 
  Average
Price Per
Common
Share
 
 
  Number   Percent   Amount   Percent  

Selling shareholder

                      % $                   % $         

New investors in this offering

            %           % $    

Total

            % $         %      

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OUR CASH DISTRIBUTION POLICY AND RESTRICTIONS ON DISTRIBUTIONS

        You should read the following discussion of our cash distribution policy in conjunction with the more detailed information regarding the factors and assumptions upon which our cash distribution policy is based in "—Assumptions and Considerations Related to the Estimated Cash Available for Distribution Based upon Adjusted EBITDA of Antero Midstream" below. In addition, you should read "Cautionary Statement Regarding Forward-Looking Statements" and "Risk Factors" for information regarding statements that do not relate strictly to historical or current facts and material risks inherent in our and Antero Midstream's business.

        For additional information regarding our historical operating results, you should refer to Antero Midstream's audited historical financial statements included elsewhere in this prospectus. In addition, please read "Cautionary Statement Regarding Forward-Looking Statements."

General

        Our Cash Distribution Policy.    The board of directors of our general partner will adopt a cash distribution policy to be effective as of the closing of this offering pursuant to which we will distribute all of our available cash on a quarterly basis. Generally, our available cash is all cash on hand at the date of determination of available cash for the distribution in respect of such quarter, after reserves for taxes and other expenses, including payments to our general partner and its affiliates. The board of directors of our general partner may change our distribution policy at any time and from time to time. Our partnership agreement will not restrict our ability to borrow to pay distributions.

        Our cash flow is generated solely from distributions we receive from IDR LLC. IDR LLC receives all of its cash flows from distributions on the IDRs in Antero Midstream. We are therefore entirely dependent upon the ability of Antero Midstream to make cash distributions to its partners. In addition, we currently have no independent operations. Accordingly, we believe we will initially have low ongoing cash requirements. Our cash distribution policy reflects a judgment that our shareholders will be better served by our distributing rather than retaining our cash available for distribution.

        We expect our quarterly cash distributions for the twelve-month period ending June 30, 2018 to total $            per common share.

        Restrictions and Limitations on Our Cash Distribution Policy.    There is no guarantee that our shareholders will receive quarterly distributions from us, that we will receive quarterly distributions from IDR LLC or that IDR LLC will receive quarterly distributions from Antero Midstream. Neither we nor Antero Midstream have a legal obligation to pay distributions.

        Our and Antero Midstream's cash distribution policy are subject to certain restrictions. These restrictions include the following:

    The amount of cash that Antero Midstream can distribute each quarter is subject to restrictions under its revolving credit facility and the indenture governing its outstanding senior notes, which prohibits distributions on, or purchases or redemptions of, units if any default or event of default is continuing. These debt agreements contain various covenants limiting Antero Midstream's ability to, among other things, incur indebtedness if certain financial ratios are not maintained, grant liens, engage in transactions with affiliates, enter into sale-leaseback transactions, and sell substantially all of its assets or enter into a merger or consolidation. In addition, these debt agreements treat a change of control or failure to maintain a certain debt coverage ratio as an event of default. In addition, a default under Antero Midstream's revolving credit facility will be treated as a default under the indenture governing its outstanding senior notes and vice versa. These financial tests and covenants are described in this prospectus under the heading "Management's Discussion and Analysis of Financial Condition and Results of Operations—Antero Midstream's Liquidity and Capital Resources" and in Note 4 to Antero Midstream's Consolidated Financial Statements.

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      Should Antero Midstream be unable to comply with the restrictions under its debt agreements, Antero Midstream would be prohibited from making cash distributions to IDR LLC, which in turn would prevent IDR LLC from making cash distributions to us.

    Antero Midstream's general partner has authority under Antero Midstream's partnership agreement to cause Antero Midstream to retain cash that Antero Midstream could otherwise distribute by changing Antero Midstream's distribution policy as appropriate to comply with applicable law or any agreement binding on Antero Midstream as well as its subsidiaries and to provide for future cash distributions to Antero Midstream's unitholders. We own all of the interests in and appoint all of the members of the board of directors of the general partner of Antero Midstream. However, the board of directors of the general partner of Antero Midstream has sole authority to determine the cash distribution policy of Antero Midstream, and we are unable to control the amount of any cash distributed or retained by Antero Midstream. The retention of additional cash amounts would result in a reduction in cash distributions that IDR LLC would otherwise receive from Antero Midstream, which in turn could result in a reduction in cash distributions to you from levels we currently anticipate pursuant to our stated cash distribution policy. The board of directors of Antero Midstream's general partner could change its distribution policy and such determination will be binding on Antero Midstream's unitholders as well as the holders of its general partner interest and IDRs.

    Our general partner will have the authority to establish cash reserves for the prudent conduct of our business, including for future cash distributions to our shareholders, and the establishment of or increase in those reserves could result in a reduction in cash distributions from levels we currently anticipate pursuant to our stated cash distribution policy. Our partnership agreement does not set a limit on the amount of cash reserves that our general partner may establish. While we have not historically established cash reserves, each quarter commencing with the quarter ending March 31, 2017 we expect to retain from the cash distributions we receive on the Series A Units in IDR LLC an amount corresponding to the aggregate amount of all make-whole distributions IDR LLC will be required to pay with respect to newly-vested Series B Units for such quarter. This amount will vary over time and will depend on the number of unvested Series B Units outstanding; however, we do not expect the amount of cash we retain in any quarter to exceed 6% of Antero Midstream's cash distributions on its IDRs with respect to such quarter. Because we do not pay a fixed quarterly distribution, the amount of cash we retain to pay distributions to our shareholders corresponding to the make-whole distributions IDR LLC pays to holders of newly-vested Series B Units will not result in a shortfall in our cash available for distribution. For more information on the Series B Units and the make-whole distributions, please read "—Series B Units." Other than cash retained with respect to such distributions, we currently do not anticipate any other cash reserves.

    Prior to making any distribution on the common shares, we will reimburse our general partner and its affiliates for all direct and indirect expenses they incur on our behalf. Our partnership agreement does not set a limit on the amount of expenses for which our general partner and its affiliates may be reimbursed. These expenses include salary, bonus, incentive compensation and other amounts paid to persons who perform services for us or on our behalf and expenses allocated to our general partner by its affiliates. Our obligations to reimburse our general partner and its affiliates are governed by our partnership agreement and the services agreement that we expect to enter into with our general partner, IDR LLC, and Antero Resources. The reimbursement of expenses and payment of fees, if any, to our general partner and its affiliates will reduce the amount of cash available to pay distributions to our shareholders.

    Even if our cash distribution policy is not modified or revoked, the amount of distributions we pay under our cash distribution policy and the decision to make any distribution is determined by our general partner.

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    Under Section 17-607 of the Delaware Revised Uniform Limited Partnership Act and Section 18-607 of the Delaware Limited Liability Company Act, as applicable, an entity may make a distribution if such distribution would cause that entity's liabilities to exceed the fair value of its assets.

    We may lack sufficient cash to pay distributions to our shareholders due to increases in our, IDR LLC's or Antero Midstream's operating or general and administrative expenses, principal and interest payments on debt, working capital requirements, taxes and other anticipated cash needs.

        Our Cash Distribution Policy Limits Our Ability to Grow.    We expect to adopt a distribution policy pursuant to which we will generally distribute a significant percentage of our cash from operations to our shareholders on a quarterly basis, after the establishment of cash reserves and payment of our expenses. Therefore, our growth may not be as fast as businesses that reinvest most or all of their cash to expand ongoing operations. In fact, because currently our cash-generating assets consist solely of our interest in Antero Midstream's IDRs, our growth will be completely dependent upon Antero Midstream. The amount of cash distributions received on the IDRs is based on the per unit distribution Antero Midstream paid on each Antero Midstream common unit. Accordingly, the cash distribution on the IDRs is subject to two primary factors: (i) Antero Midstream's per unit distribution level and (ii) the number of Antero Midstream common units outstanding. An increase in either factor (assuming the other factor remains constant or increases) will generally result in an increase in the amount of cash distributions paid by Antero Midstream on the IDRs. Please read "Antero Midstream Partners LP's Cash Distribution Policy." If we issue additional common shares or we were to incur debt, the payment of distributions on those additional common shares or interest on that debt could increase the risk that we will be unable to maintain or increase our cash distribution levels. There are no limitations in our partnership agreement on our ability to incur indebtedness or to issue additional equity interests, including equity interests ranking senior to our common shares.

        Antero Midstream's Ability to Grow is Dependent on its Ability to Access External Growth Capital.    We expect to establish a distribution policy under which we expect to distribute a significant percentage of the cash we receive from Antero Midstream's distributions on the IDRs to our shareholders on a quarterly basis. In determining the amount of cash available for distribution, Antero Midstream sets aside cash reserves, which it uses, among other things, to fund a portion of its acquisitions and growth capital expenditures. Additionally, Antero Midstream has relied upon cash flow from operations, as well as external financing sources, including commercial borrowings and other debt and equity issuances, to expand its asset base to service Antero Resources' production growth and to fund its acquisition and growth capital expenditures. Accordingly, to the extent Antero Midstream does not have sufficient cash reserves or is unable to finance growth externally, its ability to grow will likely be impaired. If Antero Midstream issues additional units, the payment of distributions on those additional units may increase the risk that Antero Midstream will be unable to maintain or increase its per unit distribution level, which in turn may impact the cash we have available to distribute to our shareholders. There are no current limitations in Antero Midstream's partnership agreement on its ability to incur indebtedness or to issue additional units, including units ranking senior to its common units. The incurrence of additional debt by Antero Midstream to finance its growth strategy would result in increased interest expense to Antero Midstream, which in turn may impact the cash we have available to distribute to our shareholders.

        The IDRs May Be Limited or Modified Without Your Consent.    We own all of the capital interests in IDR LLC, which owns all of the IDRs. The IDRs entitle IDR LLC to receive increasing percentages (up to a maximum of 50%, to the extent not modified) of any cash distributed by Antero Midstream in excess of $0.1955 per Antero Midstream unit in any quarter. All of the cash flow IDR LLC receives from Antero Midstream is provided by these IDRs. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on the IDRs.

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        Antero Midstream, like other publicly traded partnerships, will generally only undertake an acquisition or expansion capital project if, after giving effect to related costs and expenses, the transaction would be expected to be accretive, meaning it would increase cash distributions per unit in future periods. Because IDR LLC currently participates in the IDRs at all levels, including the highest sharing level of 50%, an acquisition or capital project generally is less likely to be accretive to the unitholders of Antero Midstream than if the IDRs were entitled to a lower incremental cash flow. Through its interest in AMP GP, our general partner may determine, on behalf of Antero Midstream, to propose a reduction in the amount of cash distributed on the IDRs to facilitate a particular acquisition or expansion capital project. Such a reduction may relate to all of the cash flow on the IDRs or only to the expected cash flow from the transaction and may be either temporary or permanent in nature. Any such reduction in the amount of cash distributed on the IDRs will reduce the amount of cash distributions we would otherwise be able to pay to you.

        Through its interest in AMP GP, our general partner has the right to approve on behalf of Antero Midstream any waiver, reduction, limitation or modification to Antero Midstream's IDRs without the consent of our shareholders. In determining whether or not to approve any such modification, our general partner's board of directors may consider whatever information it subjectively believes is adequate in making such determination and must make such determination in "good faith" as such term is defined under applicable Delaware law and in our partnership agreement. Any determination with respect to such modification could include consideration of one or more financial cases based on a number of business, industry, economic, legal, regulatory and other assumptions applicable to the proposed transaction. The assumptions will generally involve current estimates of future conditions, which are difficult to predict and realization of many of the assumptions will be beyond our general partner's control. Moreover, the uncertainty and risk of inaccuracy associated with any financial projection will increase with the length of the forecasted period. To the extent such assumptions are not realized, the expected benefits from increases in distributions from Antero Midstream to IDR LLC may not materialize, and our distributions to our shareholders may be reduced.

Series B Units

        The amount of cash available for distribution from IDR LLC will be reduced by amounts to which the Series B Units, each representing a profits interest in IDR LLC, are entitled. IDR LLC issued 80,000 Series B Units to certain senior members of Antero Midstream's management in December 2016 and an additional 20,000 Series B Units in January 2017. The Series B Units are subject to restrictions on transfer and vest in one-third increments upon each anniversary of the vesting commencement date.

        When vested, the Series B Units are limited to proportionate participation in cash distributions paid by IDR LLC above $7.5 million per quarter until the holders of vested Series B Units receive aggregate distributions equal to up to 6% of the amount distributed in excess of $7.5 million per quarter. As of the date hereof, all 100,000 Series B Units authorized for issuance have been issued. Assuming all authorized Series B Units vest, the maximum participation would be 6% of the amount of distributed cash flow in excess of $7.5 million per quarter. The Series B Units will not be entitled to receive cash distributions until vested. However, when vesting occurs the Series B Units will receive a make-whole payment of amounts to which they would have been entitled prior to vesting. In anticipation of such make-whole distributions, each quarter we expect to retain from the cash distributions we receive on the Series A Units an amount corresponding to the aggregate amount of all make-whole distributions for such quarter.

        Additionally, the Series B Holders will have the ability to redeem vested Series B Units for our common shares pursuant to the Redemption Right. For more detail about the Series B Units, including the mandatory redemption of Series B Units under certain circumstances, please read "Organizational Structure—Reorganization—Series B Units and Redemption Right" and "Certain Relationships and Related Party Transactions—Limited Liability Company Agreement of IDR LLC."

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Our Initial Cash Distribution

        Our Cash Distribution Policy.    We expect our quarterly cash distributions for the twelve-month period ending June 30, 2018 to total $            per common share. We will pay you a prorated cash distribution for the first quarter that we are publicly traded. This prorated cash distribution will be paid for the period beginning on the closing date of this offering and ending on the last day of that fiscal quarter. Any distributions received by IDR LLC from Antero Midstream related to periods prior to the closing of this offering will be distributed to the ARI Members. We expect to pay this prorated cash distribution in                                    2017.

        Our ability to make cash distributions at this rate will be subject to the factors described above under the heading "—General—Restrictions and Limitations on Our Cash Distribution Policy." We cannot assure you that any distributions will be declared or paid by us. Please read "Risk Factors—Risks Inherent in an Investment in Us—Our cash flow will be entirely dependent upon the ability of Antero Midstream to make cash distributions on the IDRs."

        We will pay our cash distributions within        days of receiving IDR LLC's cash distribution in respect of the IDRs. If the distribution date does not fall on a business day, we will make the distribution on the business day immediately following the indicated distribution date.

        Our cash distributions will not be cumulative. Consequently, if we do not pay distributions on our common shares with respect to any fiscal quarter at the anticipated initial quarterly distribution, our shareholders will not be entitled to receive that fiscal quarter's payment in the future.

        Antero Midstream's Cash Distribution Policy.    The board of directors of the general partner of Antero Midstream has adopted a cash distribution policy for Antero Midstream. Antero Midstream's general partner's determination of available cash for distributions takes into account the possibility of establishing cash reserves in some quarterly periods that it may use to pay cash distributions in other quarterly periods, thereby enabling it to maintain relatively consistent cash distribution levels even if Antero Midstream's business experiences fluctuations in its cash from operations due to seasonal and cyclical factors. Its general partner's determination of available cash also allows Antero Midstream to maintain reserves to provide funding for its growth opportunities, and it has been the historical practice of Antero Midstream to reserve some of its available cash to fund growth projects. Antero Midstream makes its quarterly distributions from cash generated from its operations, and those distributions have grown over time as its business has grown, primarily as a result of numerous acquisitions and organic expansion projects that have been funded through external financing sources and cash from operations. For additional information about Antero Midstream's cash distribution policy, please read "Antero Midstream Partners LP's Cash Distribution Policy."

        The actual cash distributions paid by Antero Midstream to its partners occur within 60 days after the end of each quarter. Since November 2014 Antero Midstream has increased its quarterly cash distribution by approximately 65% from $0.17 per common unit, or $0.68 on an annualized basis, to $0.28 per common unit, or $1.12 on an annualized basis, for the quarter ended December 31, 2016. Such increase equates to a compound annual growth rate in Antero Midstream distributions of 28%. The following table sets forth,

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for the periods indicated, the amount of quarterly cash distributions Antero Midstream paid for each of its partnership interests, including the IDRs, with respect to the quarter indicated.

 
   
   
  Distributions    
 
 
   
   
  Limited Partners    
   
   
 
Quarter and Year
  Record Date   Distribution Date   Common
unitholders
  Subordinated
unitholders(1)
  General
partner
(IDRs)
  Total   Distributions
per limited
partner unit
 
 
   
   
  (in thousands, except per
share amounts)

   
   
   
 

Q4 2014(2)

  February 13, 2015     February 27, 2015   $ 7,161   $ 7,161   $   $ 14,322   $ 0.0943  

Q1 2015

  May 13, 2015     May 27, 2015   $ 13,669   $ 13,669   $   $ 27,338   $ 0.1800  

Q2 2015

  August 13, 2015     August 27, 2015   $ 14,429   $ 14,429   $   $ 28,858   $ 0.1900  

Q3 2015

  November 11, 2015     November 30, 2015   $ 20,470   $ 15,568   $ 295   $ 36,333   $ 0.2050  

*     

  November 12, 2015     November 20, 2015   $ 397   $   $   $ 397   $
*
 

  Total 2015   $ 56,126   $ 50,827   $ 295   $ 107,248        

Q4 2015

  February 15, 2016     February 29, 2016   $ 22,048   $ 16,708   $ 969   $ 39,725   $ 0.2200  

Q1 2016

  May 11, 2016     May 25, 2016   $ 23,556   $ 17,846   $ 1,850   $ 43,252   $ 0.2350  

Q2 2016

  August 10, 2016     August 24, 2016   $ 25,059   $ 18,985   $ 2,731   $ 46,775   $ 0.2500  

Q3 2016

  November 10, 2016     November 24, 2016   $ 26,901   $ 20,124   $ 4,820   $ 51,845   $ 0.2650  

*     

  November 12, 2016     November 18, 2016   $ 849   $   $   $ 849   $
*
 

  Total 2016   $ 98,413   $ 73,663   $ 10,370   $ 182,446        

Q4 2016

  February 1, 2017     February 8, 2017   $ 28,827   $ 21,264   $ 7,543   $ 57,634   $ 0.2800  

  Total 2017   $ 28,827   $ 21,264   $ 7,543   $ 57,634        

*
Distribution equivalent rights on units that vested under the Antero Midstream LTIP.

(1)
On February 9, 2017, in connection with the payment of the fourth quarter 2016 quarterly distribution, all of the subordinated units in Antero Midstream converted into common units on a one-for-one basis.

(2)
Distribution represents a prorated portion of the Partnership's minimum quarterly distribution of $0.17 per unit, based upon the number of days after the closing of the Partnership's initial public offering on November 10, 2014 through December 31, 2014.

Overview of Presentation

        In the sections that follow, we present the basis for our belief that we will be able to pay our initial quarterly distribution of $            per common share for each quarter during the twelve-month period ending June 30, 2018. In those sections, we present:

    our "Unaudited Pro Forma Cash Available for Distribution for the Years Ended December 31, 2015 and 2016," in which we present the amount of available cash we would have had available for distribution to our shareholders on a pro forma basis for the years ended December 31, 2015 and 2016; and

    our "Estimated Cash Available for Distribution Based upon Adjusted EBITDA of Antero Midstream Partners LP" in which we present our estimate of the minimum amount of Antero Midstream Adjusted EBITDA necessary for Antero Midstream to pay distributions to its partners, including IDR LLC, which would enable us to have sufficient available cash to pay our aggregate annualized quarterly distribution during the twelve-month period ending June 30, 2018 on all of the common shares expected to be outstanding upon completion of this offering.

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Unaudited Pro Forma Cash Available for Distribution for the Years Ended December 31, 2015 and 2016

        We would not have had a cash distribution for the year ended December 31, 2015 and our pro forma cash available for distribution for the year ended December 31, 2016 would have been approximately $9 million.

        Pro forma cash available for distribution includes the annual fee we will pay Antero Resources for general and administrative services, which we expect will initially be $           million per year and will be subject to annual adjustment, and estimated direct annual expenses of approximately $           million per year for recurring costs associated with being a separate publicly traded entity, including expenses associated with (i) compensation for new directors, (ii) incremental director and officer liability insurance, (iii) listing on the NYSE, (iv) investor relations, (v) legal services, (vi) tax services and (vii) accounting services. We will be responsible for all of these direct expenses, including income taxes payable by us. Please read "Certain Relationships and Related Party Transactions—Services Agreement."

        Our Predecessor's financial statements are based on the equity method of accounting. However, our ability to make distributions to our common shareholders is ultimately dependent on the financial and operating results of Antero Midstream. As such, the pro forma estimated amounts, upon which pro forma cash available for distribution is based, were derived from the audited and unaudited financial statements of Antero Midstream included elsewhere in this prospectus rather than those of our Predecessor. However, cash available for distribution is generally a cash accounting concept, while our financial statements have been prepared on an accrual basis. We derived the amounts of pro forma cash available for distribution in the manner described in the table below.

        The following table illustrates, on a pro forma basis, for the years ended December 31, 2015 and 2016, the amount of cash that would have been available for distributions to our shareholders. Certain of the pro forma adjustments presented below are explained in the accompanying footnotes.

 
  Year
Ended December 31,
2015
  Year
Ended December 31,
2016
 
 
  ($ in millions, except amounts per common
share)

 

Antero Midstream Partners LP

             

Operating revenue:

  $ 387   $ 590  

Operating expenses:

   
 
   
 
 

Direct operating

    79     162  

General and administrative (including $23 and $26 of equity-based compensation for the years ended December 31, 2015 and 2016, respectively)

    51     54  

Depreciation

    87     100  

Accretion of contingent acquisition consideration

    3     16  

Total operating expenses

    220     332  

Operating income:

   
167
   
258
 

Interest expense, net

    (8 )   (22 )

Equity in earnings of unconsolidated affiliates

        1  

Net income and comprehensive income

    159     237  

Pre-Water Acquisition net income attributed to parent

    (40 )    

General partner interest in net income attributable to incentive distribution rights            

    (1 )   (17 )

Limited partners' interest in net income

    118     220  

Net income

  $ 159   $ 237  

Interest expense

    8     22  

Depreciation expense

    87     100  

Accretion of contingent acquisition consideration

    3     16  

Equity-based compensation

    23     26  

Equity in earnings of unconsolidated affiliates

        (1 )

Distributions from unconsolidated affiliates

        8  

Gain on sale of assets

        (4 )

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  Year
Ended December 31,
2015
  Year
Ended December 31,
2016
 
 
  ($ in millions, except amounts per common
share)

 

Adjusted EBITDA

    280     404  

Pre-Water Acquisition net income attributed to parent

    (40 )    

Pre-Water Acquisition depreciation expense attributed to parent

    (19 )    

Pre-Water Acquisition equity-based compensation expense attributed to parent

    (4 )    

Pre-Water Acquisition interest expense attributed to parent            

    (2 )    

Adjusted EBITDA attributable to Antero Midstream

    215     404  

Cash interest paid, net-attributable to Antero Midstream

    (5 )   (14 )

Income tax withholding upon vesting of Antero Midstream equity-based compensation awards

    (5 )   (5 )

Cash reserved for bond interest payments(1)

        (10 )

Maintenance capital expenditures(2)

    (13 )   (22 )

Antero Midstream distributable cash flow

  $ 192   $ 353  

Antero Midstream distributable cash flow coverage ratio

    1.45 x   1.76 x

Distributions to Antero Midstream unitholders

   
 
   
 
 

Distributions to common and subordinated unitholders

  $ 131   $ 183  

Distributions on IDRs

    1     17  

Total aggregate distributions

  $ 132   $ 200  

Antero Midstream GP LP

             

Cash distributions from Antero Midstream Partners LP

  $ 1   $ 17  

Less:

             

General and administrative(3)

    2     3  

Income taxes(4)

    (1 )   5  

Estimated cash available for distribution

  $   $ 9  

Aggregate estimated cash distribution per common share (          common shares)

  $     $    

(1)
Cash reserved for bond interest payments represents accrued interest expense on Antero Midstream's 5.375% senior notes due 2024 outstanding during the period that is paid on a semi-annual basis on March 15th and September 15th of each year.

(2)
Maintenance capital expenditures represent that portion of Antero Midstream's estimated capital expenditures associated with (i) the connection of new wells to Antero Midstream's gathering and compression systems that Antero Midstream believes will be necessary to offset the natural production declines Antero Resources will experience on its wells over time and (ii) water delivery to new wells necessary to maintain the average throughput volume on Antero Midstream's systems.

(3)
Estimated incremental general and administrative costs associated with being a publicly traded entity.

(4)
Assumes 38% effective income tax rate.

Estimated Cash Available for Distribution Based upon Adjusted EBITDA of Antero Midstream Partners LP

        We forecast that our estimated cash available for distribution during the twelve-month period ending June 30, 2018 will be approximately $60 million. This amount represents an increase of $51 million and $60 million as compared to $9 million pro forma cash available for distribution for the year ended December 31, 2016, and no pro forma cash available for distribution for the year end December 31, 2015. As detailed below, this substantial increase in cash available for distribution is driven by the substantial increase in demand for Antero Midstream's gathering, compression, processing, fractionation and water services, resulting in increases in Antero Midstream's distributions. The IDRs represent the right to receive increasing percentages (up to a maximum of 50%) of any cash distributed by Antero Midstream in excess of $0.1955 per Antero Midstream common unit per quarter, including 50% of all incremental cash distributed by Antero Midstream per quarter after Antero Midstream has distributed $0.2550 per unit in respect of its common units for that quarter. As Antero Midstream grows its distributions, we will be entitled to a disproportionate share of that growth, which we believe we provide us with significantly more cash available for distribution to our shareholders during the twelve-month period ending June 30, 2018 than would have been available for the year ended December 31, 2015 or the year ended December 31, 2016. For example, the IDRs received a distribution of $2.7 million for the second quarter of 2016,

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$4.8 million for the third quarter of 2016 and $7.5 million for the fourth quarter of 2016 and will continue to receive increasing distributions as Antero Midstream's total cash available for distribution increases.

        Please read "—Assumptions and Considerations Related to the Estimated Cash Available for Distribution Based upon Adjusted EBITDA of Antero Midstream Partners LP" for a discussion of the material assumptions underlying our belief that Antero Midstream will be able to generate sufficient Adjusted EBITDA to provide us with the forecasted increases in cash distributions. Although we believe that these assumptions are reasonable in light of our current expectations regarding future events, the assumptions underlying the distributions to be received from Antero Midstream are inherently uncertain and are subject to significant business, economic, regulatory and competitive risks and uncertainties that could cause actual results to differ materially from those we anticipate. If the estimated Adjusted EBITDA of Antero Midstream is not achieved, we may not be able to pay the annual distribution on all of our common shares. However, we estimate that cash available for distribution could be approximately 75% of the forecast presented below and still permit Antero Midstream to declare its forecasted annual cash distribution of $1.510 per unit given the anticipated $129 million of excess cash available for distribution reflected in the forecast period. The statement that we believe that cash distributions from Antero Midstream will be sufficient to allow us to pay the annual distribution on all of our common shares for the twelve-month period ending June 30, 2018 should not be regarded as a representation by us or the underwriters or any other person that we will declare and make such distributions.

        The accompanying prospective financial information was prepared in accordance with Antero Midstream's and our accounting policies; however, it was not prepared with a view toward compliance with the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. In the view of our management, the prospective financial information has been prepared on a reasonable basis, reflects the best currently available estimates and judgments, and presents, to the best of management's knowledge and belief, the assumptions on which we base our belief that Antero Midstream can generate the estimated Adjusted EBITDA necessary for us to have sufficient cash available for distributions to pay the initial quarterly distribution to all of our shareholders. This information is not fact and should not be relied upon as being necessarily indicative of future results, and readers of this prospectus are cautioned not to place undue reliance on the prospective financial information.

        The prospective financial information included in this prospectus has been prepared by, and is the responsibility of, our management. KPMG LLP has neither examined nor compiled the accompanying prospective financial information and, accordingly, KPMG LLP does not express an opinion or any other form of assurance with respect thereto. The KPMG LLP report included in this prospectus relates only to our Predecessor's historical financial information. Such report does not extend to the prospective financial information and should not be read to do so.

        When reading these sections, you should keep in mind the risk factors and other cautionary statements under "Risk Factors" in this prospectus. Any of these factors or the other risks discussed in this prospectus could cause our financial condition and consolidated results of operations to vary significantly from those set forth below.

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        We do not undertake any obligation to release publicly the results of any future revisions we may make to the estimated cash available for distribution or to update our estimate to reflect events or circumstances after the date of this prospectus.

 
  Twelve-Month
Period Ending
June 30,
2018
 
 
  (In millions
except per
share data)

 

Antero Midstream Partners LP
       

Operating revenues:

  $ 822  

Operating expenses:

   
 
 

Direct operating

    186  

General and administrative (including $28 of equity-based compensation)

    56  

Depreciation

    123  

Accretion of contingent acquisition consideration

    16  

Total operating expenses

    381  

Operating income

    442  

Interest expense, net

    57  

Equity in earnings of unconsolidated affiliates

    (29 )

Net income and comprehensive income

  $ 414  

Interest expense, net(a)

    57  

Depreciation expense

    123  

Accretion of contingent acquisition consideration

    16  

Equity-based compensation

    28  

Cash distributions received from unconsolidated affiliates

    36  

Equity in earnings of unconsolidated affiliates

    (29 )

Adjusted EBITDA(b)

  $ 646  

Cash interest paid, net

    (57 )

Cash reserved for payment of income tax withholding upon vesting of Antero Midstream equity-based compensation awards

    (5 )

Expansion capital expenditures

    (580 )

Maintenance capital expenditures(c)

    (70 )

Borrowings and retained cash flow to fund expansion capital expenditures(d)

    580  

Estimated cash available for distribution

  $ 513  

Excess cash available for distribution

    129  

Antero Midstream distributable cash flow coverage ratio(e)

    1.34x  

Distributions to Antero Midstream Partners LP unitholders

       

Assumed average annual Antero Midstream distribution per unit

  $ 1.51  

Distributions to common and subordinated unitholders

    281  

Distributions to IDR LLC

    104  

Total distributions to Antero Midstream Partners LP unitholders(f)

  $ 385  

Antero IDR Holdings LLC
       

Cash distributions from Antero Midstream Partners LP

  $ 104  

Cash distributions to AMGP

    100  

Cash distributions on Series B Units of IDR LLC

    4  

Antero Midstream GP LP
       

Cash distributions from Antero IDR Holdings LLC

  $ 100  

Less:

       

General and administrative

    2  

Income taxes(g)

    37  

Cash reserves(h)

     

Estimated cash available for distribution

  $ 60  

Aggregate estimated cash distribution per common share (        common shares)

  $    

(a)
Interest expense and cash interest cost assumes additional borrowings on Antero Midstream's revolving credit facility to fund approximately $451 million of expansion capital expenditures during the forecast period.

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(b)
Antero Midstream defines Adjusted EBITDA as net income before interest expense, depreciation expense, accretion of contingent acquisition consideration, equity based compensation, equity in earnings of unconsolidated affiliates, distributions from unconsolidated affiliates and gain on sale of assets.

(c)
Maintenance capital expenditures are cash expenditures (including expenditures for the construction or development of new capital assets or the replacement, improvement or expansion of existing capital assets) made to maintain, over the long term, Antero Midstream operating capacity or revenue. Examples of maintenance capital expenditures are expenditures to repair, refurbish and replace pipelines, to connect new wells to maintain gathering and compression and fresh water delivery throughput, to maintain equipment reliability, integrity and safety and to address environmental laws and regulations.

(d)
Assumes incremental borrowings of $451 million under Antero Midstream's revolving credit facility for, and retained cash flow from operations of $129 million generated during, the twelve month period ending June 30, 2018.

(e)
Antero Midstream defines distributable cash flow as Adjusted EBITDA less pre-acquisition net income attributable to the parent, depreciation expense attributable to the parent, equity based compensation attributable to the parent, interest expense attributable to the parent, cash interest paid, income tax withholding payments and cash reserved for payments upon vesting of equity-based compensation awards, cash reserved for bond interest payments and ongoing maintenance capital expenditures paid, excluding pre-acquisition amounts attributable to the parent, plus cash to be received from unconsolidated affiliates.

(f)
Assumes 185,793,884 Antero Midstream common units outstanding throughout the forecast period.

(g)
Assumes 38% effective income tax rate.

(h)
Assumes no reserves are established by our general partner. Please read "Assumptions and Considerations—Distributions from Antero Midstream Partners LP to Antero IDR Holdings LLC and Antero Midstream GP LP—Distributions on Series B Units."

Assumptions and Considerations

        Our belief that Antero Midstream will generate Adjusted EBITDA of $646 million for the twelve-month period ending June 30, 2018 and that we will have $60 million of available cash to pay our forecasted quarterly distributions on all of our common shares for the twelve-month period ending June 30, 2018 is based on the following assumptions about Antero Midstream's operating performance. Such beliefs are also supported by Antero Resources' projected net daily production guidance of approximately 2.2 Bcfe/d, a 20% to 25% increase over its 2016 guidance of 1.8 Bcfe/d, and Antero Midstream's recent announcement that it expects (i) 2017 distribution growth to be 28% to 30% as compared to the prior year and (ii) distributable cash flow coverage of 1.30x to 1.45x.

        Antero Midstream has two operating segments: (i) gathering and processing and (ii) water handling and treatment. The following table compares the historical segment Adjusted EBITDA for the twelve months ended December 31, 2016 to the forecasted segment Adjusted EBITDA for the twelve-month period ending June 30, 2018.

 
  Year
Ended
December 31,
2016
  Twelve-Month
Period Ending
June 30,
2018
  Increase  
 
  ($ in millions)
   
 

Antero Midstream Partners LP

                   

Segment Adjusted EBITDA

                   

Gathering and Processing

  $ 264   $ 418     58 %

Water Handling and Treatment

    140     228     63 %

Total Adjusted EBITDA

  $ 404   $ 646     60 %

Gathering and Processing Segment

        Antero Midstream's gathering and processing segment operations consist of long-term, fee-based activities including low-pressure gathering, compression, high-pressure gathering, processing, fractionation and condensate gathering, limiting its direct exposure to commodity price risk. Antero Midstream's gathering and processing segment also includes distributions received from unconsolidated affiliates from its 50% equity interest in the Joint Venture and its 15% non-controlling equity interest in Stonewall Gas Gathering LLC, for which Antero Resources is an anchor shipper. Substantially all of Antero Midstream's

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Adjusted EBITDA in its gathering and processing segment for both the year ended December 31, 2016 and twelve-month forecast period ending June 30, 2018 is derived from Antero Resources.

        The increase in forecasted gathering and processing segment Adjusted EBITDA is driven by an increase in forecasted low-pressure gathering, compression and high-pressure gathering volumes from completions corresponding to Antero Resources' development plan, as well as production from existing wells on Antero Midstream's system. Additionally, the increase in forecasted gathering and processing segment Adjusted EBITDA is driven by the contribution from existing processing and fractionation attributable to the Joint Venture as well as additional processing and fractionation capacity expected to be placed in service during the forecast period. Antero Resources expects to operate an average of four drilling rigs in the Marcellus Shale and three drilling rigs in the Utica Shale during 2017, which is expected to result in net production growth at Antero Resources of 20% to 25% as compared to 2016 production guidance of 1.8 Bcfe/d. Additionally, since Antero Resources' completion activity is primarily focused on acreage dedicated to Antero Midstream for gathering and compression services, Antero Midstream expects growth in throughput volumes on a percentage basis in excess of Antero Resources' net production growth forecast of 20% to 25%. Antero Midstream's forecasted gathering and compression Adjusted EBITDA for the twelve-month period ending June 30, 2018 excludes the potential impact from third-party low-pressure gathering, compression and high-pressure gathering volumes. Antero Midstream has not assumed any impact from minimum volume commitments in the gathering and processing segment for the twelve-month period ending June 30, 2018 because it expects Antero Resources' aggregate volumes during the period to be in excess of any such minimum volume commitments.

        Antero Midstream expects to have 214 miles of low-pressure and 153 miles of high-pressure pipelines in service as of June 30, 2018, respectively, in the Marcellus and Utica Shales, compared to 180 miles of low-pressure pipelines and 140 miles of high-pressure pipelines expected to be in service as of June 30, 2017. Additionally, Antero Midstream expects to have 2.2 Bcf/d of compression capacity in service in the Marcellus and Utica Shales as of June 30, 2018, compared to 1.4 Bcf/d of capacity in service as of June 30, 2017.

Water Handling and Treatment Segment

        Antero Midstream's water handling and treatment segment consists of long-term fee based activities including fresh water delivery used in completion activity and water handling services for the disposal and treatment of produced and flowback wastewater, including the Antero Clearwater Facility currently under construction. All of Antero Midstream's Adjusted EBITDA in its water handling and treatment segment for both the year ended December 31, 2016 and twelve-month period ending June 30, 2018 is derived from Antero Resources.

        The increase in forecasted water handling and treatment segment Adjusted EBITDA is driven by an increase in revenues from increased fresh water delivery and produced and flowback wastewater volumes from Antero Resources' planned completions over the forecast period. Antero Resources expects to complete 135 wells in the Marcellus Shale and 35 wells in the Utica Shale in 2017 using enhanced completions, which utilize more proppant and water when compared to previous completions, driving increased demand for Antero Midstream's water services. Additionally, the increase in forecasted water handling and treatment segment EBITDA is driven by the expected commencement of operations of the Antero Clearwater Facility during the fourth quarter of 2017. Antero Midstream's forecasted water handling and treatment segment Adjusted EBITDA for the twelve-month period ending June 30, 2018 excludes the impact from potential third-party fresh water or wastewater volumes. Antero Midstream has not assumed any impact from minimum volume commitments in the water handling and treatment segment for the twelve-month period ending June 30, 2018 because it expects Antero Resources' aggregate volumes during the period to be in excess of any such minimum volume commitments.

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        Antero Midstream expects to have 349 miles of surface and permanent buried pipelines in the Marcellus and Utica Shales in service as of June 30, 2018, compared to 299 miles of surface and permanent buried pipelines in service as of June 30, 2017. Additionally, Antero Midstream expects to have 41 fresh water storage impoundments in service in the Marcellus and Utica Shales in service as of June 30, 2018, compared to 36 fresh water storage impoundments in service as of June 30, 2017. Additionally, Antero Midstream expects the 60,000 Bbl/d Antero Clearwater Facility to be placed in service in the fourth quarter of 2017.

Operating Revenues

        Antero Midstream generates 100% of its revenue through long-term, fixed-fee contracts. We forecast Antero Midstream will have operating revenues for the twelve-month period ending June 30, 2018 of approximately $822 million compared to $590 million for the year ended December 31, 2016. Operating revenues are forecast to increase for the twelve-month period ending June 30, 2018 due to increased throughput volumes in the gathering and processing and water handling and treatment segments.

        The following table compares Antero Midstream's historical fees for the year ended December 31, 2016 to the contract fees for the twelve-months ending June 30, 2018.

 
  Year
Ended
December 31,
2016
  Twelve-Month
Period Ending
June 30,
2018(1)
 

Low-pressure gathering fees ($/Mcf)

  $ 0.31   $ 0.32  

Compression fees ($/Mcf)

  $ 0.19   $ 0.19  

High-pressure gathering fees ($/Mcf)

  $ 0.19   $ 0.19  

Condensate gathering fees ($/Bbl)

  $ 4.17   $ 4.28  

Fresh water delivery fee ($/Bbl)

  $ 3.68   $ 3.76  

Advanced Wastewater Treatment Fee (S/Bbl)

      $ 4.09  

(1)
Assumes a 2.0% CPI-based adjustment pursuant to the terms of the applicable contracts with Antero Resources.

Direct Operating Expenses

        We assume Antero Midstream will have direct operating expenses for the twelve-month period ending June 30, 2018 of approximately $186 million compared to $162 million for the year ended December 31, 2016. Direct operating expenses are forecast to increase for the twelve-month period ending June 30, 2018 due to significantly higher activity levels and increased operating costs associated with Antero Midstream's growth projects including increased pipeline mileage, additional compressor stations, increased fresh water infrastructure and the commencement of operations at the Antero Clearwater Facility. Additionally, we expect direct operating expenses to increase at a slower rate than operating revenues due to the fixed cost nature of a majority of our direct operating expenses, as well as the elimination of a significant portion of other fluid handling services operating expenses once the Antero Clearwater Facility is placed into service and associated treatment fees are recognized as revenue.

General and Administrative Expenses

        Antero Midstream's general and administrative expense will primarily consist of direct general and administrative expenses incurred by Antero Midstream and payments it makes to Antero in exchange for the provision of general and administrative services. Antero Midstream estimates that general and administrative expenses for the twelve-month period ending June 30, 2018 will be $56 million (including $28 million of non-cash stock compensation expense) as compared to $54 million (including $26 million of

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non-cash stock compensation expense) for the year ended December 31, 2016. General and administrative expenses are forecast to increase primarily due to an increase in non-cash stock compensation expense.

Depreciation Expenses

        We estimate that Antero Midstream's depreciation expenses for the twelve-month period ending June 30, 2018 will be $123 million as compared to $100 million for the year ended December 31, 2016. Depreciation expenses are forecast to increase due to the additional gathering, compression and water services assets placed in service during the forecast period.

Accretion of Contingent Acquisition Consideration

        In connection with the Water Acquisition, Antero Midstream agreed to pay Antero Resources (i) $125 million in cash if it delivers an average of 161,000 barrels per day or more of fresh water during the period between January 1, 2017 and December 31, 2019 and (ii) an additional $125 million in cash if it delivers an average of 200,000 barrels per day or more of fresh water during the period between January 1, 2018 and December 31, 2020. At the time of the Water Acquisition, Antero Midstream recorded a liability for the discounted net present value of the contingent acquisition consideration, and as time passes, recognizes accretion expense. This liability is revalued each reporting period for any changes in assumptions. Accretion of contingent acquisition consideration is forecasted to increase due to twelve months of contingent acquisition consideration accretion incurred during the forecast period. We estimate that Antero Midstream's accretion of contingent acquisition consideration expense for the twelve-month period ending June 30, 2018 will be $15 million as compared to $16 million for the year ended December 31, 2016.

Interest Expense

        We estimate that Antero Midstream's interest expense will be approximately $57 million for the twelve-month period ending June 30, 2018 as compared to $22 million for the year ended December 31, 2016. This interest expense for the twelve-month period ending June 30, 2018 is based on the following assumptions:

    the actual interest charged on $650 million aggregate principal amount of Antero Midstream's 5.375% senior notes due 2024 issued in September 2016; and

    An average revolving credit facility balance of approximately $676 million during the period at an average interest rate of approximately 3%. The average interest rate is a weighted average interest rate calculated by reference to the greater of the applicable base rate or Eurodollar rate, plus any applicable spread thereto, determined in accordance with Antero Midstream's revolving credit facility.

Equity in Earnings of Unconsolidated Affiliates

        We estimate that Antero Midstream's equity in earnings of unconsolidated affiliates for the twelve-month period ending June 30, 2018 will be $29 million as compared to $1 million for the year ended December 31, 2016. Equity in earnings of unconsolidated affiliates is forecast to increase due to a full year contribution of the equity earning in Stonewall Gas Gathering LLC and the entry into the Joint Venture.

Capital Expenditures

        We estimate that Antero Midstream's capital expenditures will be $650 million for the twelve-month period ending June 30, 2018, $421 million of which will be invested in gathering and $115 million will be invested in water handling and treatment, including the completion of the Antero Clearwater Facility. Additionally, Antero Midstream expects to invest $114 million in the Joint Venture during the twelve

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months ending June 30, 2018. Of the total $650 million in capital expenditures, $580 million will be expansion capital expenditures and the remaining $70 million will be maintenance capital expenditures, as compared to $416 million for the year ended December 31, 2016, of which $394 million represented expansion capital expenditures and $22 million represented maintenance capital expenditures. Capital expenditures are forecast to increase due to Antero Midstream's forecasted investment in gathering, compression, processing, fractionation and water infrastructure to support the production growth of Antero Resources.

Financing

        Antero Midstream expects to fund all of its capital expenditures, including capital investments in the Joint Venture during the forecast period, with a combination of cash on hand, cash flow from operations and borrowings under its existing $1.5 billion revolving credit facility. Antero Midstream's estimated interest expense and average borrowings during the forecast period reflect funding approximately $451 million of its capital expenditures during the forecast period with available borrowing capacity under its revolving credit facility and the remaining approximately $200 million with cash flow from operations. As of December 31, 2016, Antero Midstream had $1.2 billion of available borrowing capacity under its revolving credit facility. As of June 30, 2018, Antero Midstream expects to have approximately $650 million of available borrowing capacity.

        In addition, as of December 31, 2016, Antero Midstream had approximately $185 million of available capacity under its at-the-market equity offering program; however, for purpose of this forecast, Antero Midstream has assumed no additional proceeds from equity issuances under its at-the-market equity offering program during the forecast period.

        As a result, Antero Midstream expects to have approximately $185 million of available capacity under its at-the-market equity offering program as of June 30, 2018.

Cash distributions received from unconsolidated affiliates

        We estimate that Antero Midstream's cash distributions received from unconsolidated affiliates for the twelve-month period ending June 30, 2018 will be $36 million as compared to $8 million for the year ended December 31, 2016. We estimate Antero Midstream will receive $21 million of cash distributions related to its ownership in the Joint Venture and $15 million of cash distributions related to its ownership in Stonewall Gas Gathering LLC. Cash distributions received from unconsolidated affiliates are forecast to increase due to a full year contribution of the earnings in the Joint Venture and Stonewall Gas Gathering LLC. Additionally, Antero Midstream's $30 million capital contribution to Stonewall Gas Gathering LLC used to repay existing borrowings during the fourth quarter of 2016 permitted future distributions to equity interest holders.

Cash reserved for payment of income tax withholding upon vesting of Antero Midstream equity-based compensation awards

        We estimate that Antero Midstream's cash reserved for payment of income tax withholding upon vesting of Antero Midstream equity-based compensation awards for the twelve-month period ending June 30, 2018 will be $5 million as compared to $6 million for the year ended December 31, 2016. We estimate that Antero Midstream's cash reserved for payment of income tax withholding upon vesting of Antero Midstream equity-based compensation awards for the twelve-month period ending June 30, 2018 will be $5 million, which is relatively consistent with its $6 million cash reserve for the year ended December 31, 2016.

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Distributions from Antero Midstream Partners LP to Antero IDR Holdings LLC and Antero Midstream GP LP

Distributions on Series B Units

        We own the IDRs in Antero Midstream through our interest in IDR LLC, which we will control as managing member. IDR LLC has issued all of its capital interests to us in the form of Series A Units and has issued Series B Units, representing profits interests, to certain senior members of Antero Midstream's management team. Through our interest in IDR LLC, we receive 100% of the first $7.5 million of quarterly cash distributions paid by Antero Midstream on the IDRs. The Series B Holders will receive up to 6% of all quarterly cash distributions in excess of $7.5 million paid by Antero Midstream on the IDRs and we will receive the remainder of such distributions. The Series B Units are subject to restrictions on transfer and vest ratably over a three-year period upon each anniversary of the vesting commencement date. As Series B Units vest, each holder of such vested Series B Units will be entitled to receive a make-whole distribution corresponding to the aggregate amount of distributions such holder would have received on such Series B Units had they vested on the vesting commencement date. In anticipation of such make-whole distributions, each quarter we expect to retain from the cash distributions we receive on the Series A Units an amount corresponding to the aggregate amount of all make-whole distributions for such quarter. Each quarter, when IDR LLC pays make-whole distributions on its newly-vested Series B Units, we will distribute a corresponding amount of our retained cash to our shareholders on a pro rata basis. However, for purposes of this forecast, we have assumed that all of the Series B Units have vested and, therefore, that IDR LLC will pay the maximum 6% of quarterly cash distributions in excess of $7.5 million received from Antero Midstream on the IDRs to the holders of the Series B Units, resulting in estimated cash distributions on the Series B Units of approximately $4.2 million.

General and Administrative Expenses

        We estimate that our incremental general and administrative expenses associated with being a publicly traded partnership will be approximately $2 million for the twelve-month period ending June 30, 2018.

Income Taxes

        We estimate that our income tax expense will be $37 million for the twelve-month period ending June 30, 2018, as compared to $6 million for the year ended December 31, 2016. Our forecast assumes a tax rate of 38%. This estimated tax rate is computed by adding our effective state and local income tax rate to the maximum U.S. federal income tax rate.

Other Assumptions

        Our estimated cash available for distribution for the twelve-month period ending June 30, 2018 is based on the following significant additional assumptions:

    no cash reserves for taxes and other expenses;

    no new federal, state or local regulation of the midstream energy sector, or any new interpretation of existing regulations, that will be materially adverse to our or Antero Resources or Antero Midstream's business;

    no major adverse change in the midstream energy sector, commodity prices, capital or insurance markets or general economic conditions;

    no material accidents, weather-related incidents, unscheduled downtime or similar unanticipated events with respect to our facilities or those of third parties on which we, Antero Midstream or Antero Resources depend;

    no acquisitions or other significant expansion capital expenditures (other than as described above); and

    no substantial change in market, insurance and overall economic conditions.

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HOW WE MAKE CASH DISTRIBUTIONS

        Set forth below is a summary of the significant provisions of our partnership agreement that relate to cash distributions.

General

        While our partnership agreement provides that our general partner will make a determination as to whether to make a distribution, our partnership agreement does not require us to pay distributions at any time or in any amount. Instead, the board of directors of our general partner will adopt a cash distribution policy to be effective as of the closing of this offering that will set forth our general partner's intention with respect to the distributions to be made to shareholders. Pursuant to this cash distribution policy, we will pay our cash distributions within      days within receiving IDR LLC's cash distribution in respect of the IDRs, to the extent we have sufficient cash after establishment of cash reserves and payment of fees and expenses, including payments to our general partner and its affiliates. We expect our quarterly cash distributions for the twelve-month period ending June 30, 2018 to total $            per common share.

        The board of directors of our general partner may change our distribution policy at any time and from time to time, and even if our cash distribution policy is not modified or revoked, the amount of distributions paid under our distribution policy and the decision to make any distribution is determined by our general partner. Our partnership agreement does not contain a requirement for us to pay distributions to our shareholders, and there is no guarantee that we will pay any distribution on the common shares in any quarter.

Our Sources of Cash

        Following the completion of this offering, our only cash-generating asset will consist of all of the capital interests in IDR LLC, which owns all of the IDRs in Antero Midstream. Therefore, our cash flow and resulting ability to make distributions will be completely dependent upon the ability of Antero Midstream to make distributions in respect of its IDRs. The actual amount of cash that Antero Midstream, and correspondingly IDR LLC, will have available for distribution will primarily depend on the amount of cash Antero Midstream generates from its operations. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on the IDRs. For a description of factors that may impact our results and Antero Midstream's results, please read "Cautionary Statement Regarding Forward-Looking Statements."

        In addition, the actual amount of cash that Antero Midstream will have available for distribution will depend on other factors, some of which are beyond Antero Midstream's or our control, including:

    the level of revenue Antero Midstream is able to generate from its business;

    the level of capital expenditures Antero Midstream makes;

    the level of Antero Midstream's operating, maintenance and general and administrative expenses or related obligations;

    the cost of acquisitions, if any;

    Antero Midstream's debt service requirements and other liabilities;

    Antero Midstream's working capital needs;

    restrictions on distributions contained in Antero Midstream's debt agreements or any future debt agreements;

    Antero Midstream's ability to borrow under its revolving credit facility to make distributions; and

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    the amount, if any, of cash reserves established by each of Antero Midstream's general partner and our general partner, in their sole discretion, for the proper conduct of Antero Midstream's and our business. While neither our general partner nor Antero Midstream's general partner has established such reserves historically, we expect to retain a portion of the cash distributions we receive from IDR LLC commencing with the quarter ending March 31, 2017 in order to pay to our shareholders in future periods distributions corresponding to the make-whole distributions IDR LLC will be required to pay to holders of its newly-vested Series B Units. For more information, please read "Our Cash Distribution Policy and Restrictions on Distributions—Restrictions and Limitations on Our Cash Distribution Policy." Other than cash retained with respect to such distributions, neither our general partner nor Antero Midstream's general partner currently anticipates any other cash reserves.

Shares

        As of the closing of this offering, we will have                    common shares outstanding. For additional information regarding our common shares, please read "Description of Our Common Shares."

General Partner Interest

        Our general partner owns a non-economic general partner interest in us, which does not entitle it to receive cash distributions. Please read "Organizational Structure—Reorganization."

Distributions of Cash Upon Liquidation

        If we dissolve in accordance with the partnership agreement, we will sell or otherwise dispose of our assets in a process called a liquidation. We will first apply the proceeds of liquidation to the payment of our creditors and, thereafter, holders of our common shares would be entitled to share ratably in the distribution of any remaining proceeds.

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SELECTED HISTORICAL FINANCIAL DATA

        Prior to the formation of IDR LLC, our Predecessor, Antero Resources Midstream Management LLC, owned the general partner interest in Antero Midstream and the IDRs, and in connection with IDR LLC's formation, our Predecessor conveyed the IDRs to IDR LLC in exchange for all of the Series A Units. In connection with the Reorganization, our Predecessor will (i) convey its 100% interest in the non-economic general partner interest in Antero Midstream to AMP GP, a wholly owned subsidiary of our Predecessor and (ii) convert into a Delaware limited partnership named Antero Midstream GP LP, which will elect to be taxed as a corporation for U.S. federal income tax purposes.

        The historical financial data of our Predecessor reflect our ownership of the general partner interest in Antero Midstream through our interest in AMP GP and our ownership of the IDRs through our ownership of the capital interests of IDR LLC, which we will continue to control as managing member. We have used the equity method to account for our investment in Antero Midstream because we are not the primary beneficiary of Antero Midstream for financial reporting purposes. Additionally, we have no separate operating activities apart from those conducted by Antero Midstream, and our cash flows will consist solely of distributions from IDR LLC related to its ownership of the IDRs.

        The selected historical statements of operations and cash flow data of our Predecessor for the years ended December 31, 2015 and 2016 and the balance sheet data as of December 31, 2015 and 2016 are derived from the audited financial statements of our Predecessor included elsewhere in this prospectus.


Selected Historical Financial Table

 
  Year Ended
December 31,
 
 
  2015   2016  
 
  (in thousands,
except per share
amounts)

 

Statement of Operations Data:

             

Equity in earnings of Antero Midstream Partners LP

  $ 1,264   $ 16,944  

Interest income

        1  

Total income

    1,264     16,945  

General and administrative expense

        815  

Income before income taxes

    1,264     16,130  

Provision for income tax expense

    (483 )   (6,419 )

Net income and comprehensive income

  $ 781   $ 9,711  

Pro forma basic earnings per share

  $     $    

Pro forma diluted earnings per share

  $     $    

Balance Sheet Data (at period end):

   
 
   
 
 

Cash

  $ 72   $ 9,609  

Investment in Antero Midstream Partners LP

    969     7,543  

Total assets

    1,041     17,369  

Cash Flow Data:

   
 
   
 
 

Net cash provided by operating activities

  $ 295   $ 9,537  

Net cash used in financing activities

    (223 )    

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MANAGEMENT'S DISCUSSION AND ANALYSIS OF
FINANCIAL CONDITION AND RESULTS OF OPERATIONS

        You should read the following discussion of our historical performance, financial condition and future prospects in conjunction with our audited financial statements as of December 31, 2015 and 2016 and for the years ended December 31, 2015 and 2016, and the notes thereto, included elsewhere in this prospectus. The information provided below supplements, but does not form part of, our financial statements. This discussion contains forward-looking statements that are based on the views and beliefs of our management, as well as assumptions and estimates made by our management. Actual results could differ materially from such forward-looking statements as a result of various risk factors, including those that may not be in the control of management. For further information on these items that could impact our future operating performance or financial condition, please read the sections entitled "Risk Factors" and "Cautionary Statement Regarding Forward-Looking Statements."

Overview

        We are a Delaware limited partnership that will elect to be treated as a corporation for U.S. federal income tax purposes. We own the general partner of Antero Midstream Partners LP (NYSE: AM) ("Antero Midstream") and all of the incentive distribution rights ("IDRs") in Antero Midstream. Following the closing of this offering, we will continue to receive at least 94% of the cash distributions paid by Antero Midstream on the IDRs. Antero Midstream is a growth-oriented master limited partnership 59% owned by Antero Resources Corporation (NYSE: AR) ("Antero Resources") that was formed to own, operate and develop midstream energy infrastructure primarily to service Antero Resources' rapidly increasing production and completion activity in the Appalachian Basin's Marcellus Shale and Utica Shales located in West Virginia and Ohio. We believe that Antero Midstream's strategically located assets and integrated relationship with Antero Resources position it to be a leading Appalachian midstream provider across the midstream value chain. Through our ownership interest in Antero IDR Holdings LLC ("IDR LLC"), our subsidiary, we receive cash distributions from Antero Midstream on the IDRs. We expect these cash distributions to increase substantially over time as Antero Midstream executes its business strateg