UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

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Filed by a Party other than the Registrant  o

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o Preliminary Proxy Statement

o Confidential, for Use of the Commission Only (as permitted by Rule 14a‑6(e)(2))

o Definitive Proxy Statement

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o Soliciting Material Pursuant to §240.14a-12

Inogen, Inc.

(Name of Registrant as Specified In Its Charter)

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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on May 12,2016 INOGEN INC Meeting Information Meeting Type: Annual Meeting For holders as of: March 18, 2016 Date: May 12, 2016 Time: 10:00 AM PDT Location: 326 Bollay Drive Goleta, CA 93117 INOGEN, INC. 326 BOLLAY DRIVE GOLETA, CA 93117 You are receiving this communication because you hold shares in the above named company. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. See the reverse side of this notice to obtain proxy materials and voting instructions. 0000280703_1 R1.0.1.25

Before You Vote How to Access the Proxy Materials Proxy Materials Available to VIEW or RECEIVE: 1. Annual Report 2. Notice & Proxy Statement How to View Online: Have the information that is printed in the box marked by the arrow  XXXX XXXX XXXX XXXX (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: 2) BY TELEPHONE: 3) BY E-MAIL*: www.proxyvote.com 1-800-579-1639 sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before April 28, 2016 to facilitate timely delivery. How To Vote Please Choose One of the Following Voting Methods Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX available and follow the instructions. Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.0000280703_2 R1.0.1.25

Voting items The Board of Directors recommends you vote FOR the following: 1. Election of Class II Directors Nominees 01 Loren McFarland 02 Benjamin Anderson-Ray The Board of Directors recommends you vote FOR the following proposal: 2. To ratify the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for the year ending December 31, 2016. NOTE: In their discretion, the proxies are authorized to vote upon such other business as may properly come before the Annual Meeting or any adjournments or postponements thereof. 0000280703_3 R1.0.1.25

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