UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 1 to

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

Superior Drilling Products, Inc.

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

868153107

(CUSIP Number)

Mr. Reid Walker

3953 Maple Avenue, Suite #150,

Dallas, Texas 75219

Telephone: 214-871-8618

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

December 1, 2014

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Sections 240.13d-1(e), (f) or (g), check the following box.   ¨

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Section 240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

SCHEDULE 13D

SCHEDULE 13D

SCHEDULE 13D

Filed Pursuant to Rule 13d-1(a)

Item 1 is being amended and restated as follows:

This Statement on Schedule 13D (this “Schedule 13D”, and with respect to the disclosure contained in the Reporting Person’s originally filed Scheduled 13D, the “Originally Filed Schedule 13D”) relates to the common stock, par value $0.001 per share (the “Common Stock”), of Superior Drilling Products, Inc. (the “Issuer”), and is being filed by D4D LLC, a Texas limited liability company (“D4D”), Hard 4 Holdings, LLC, a Texas limited liability company (“Hard 4 Holdings”), the sole managing member and 50% beneficial owner of D4D, and Mr. Reid Walker (“Mr. Walker”, and collectively with D4D and Hard 4 Holdings, the “Reporting Persons”), the manager and 100% beneficial owner of Hard 4 Holdings, who personally owns additional shares purchased in the Issuer’s recent initial public offering (“IPO”). The Issuer’s principal executive offices are located at 1583 South 1700 East, Vernal, UT 84078.

Amendment No. 1 to Schedule 13D (“Amendment No. 1”) relates to the transfer of shares of Common Stock and the transfer of a warrant for the purchase of additional shares of the Issuer’s Common Stock by D4D to its members, including Hard 4 Holdings on December 1, 2014 (the “Distribution”). However, although the share certificates and warrants transferred to the members are dated as of December 1, 2014, the transfer agent did not issue certificates and the Issuer did not provide the members with warrants representing their pro rata right to purchase additional Common Stock until December 19, 2014.

No Amendment.

No Amendment.

The first Paragraph of Item 2(c) is being amended and restated as follows.

The principal business of D4D was the investment of Two Million Dollar ($2,000,000) pursuant to a bridge loan investment in SD Company, Inc., the predecessor of the Issuer (“SD Company”, and sometimes referred to as the Issuer), and Superior Drilling Products, LLC, a Utah limited liability company and the predecessor of Superior Drilling Solutions, LLC (“SDP”). Shortly following this Amendment No. 1, the members of D4D intend to dissolve D4D and liquidate any remaining assets.

No Amendment.

No Amendment.

Upon the Issuer’s IPO, consummated May 29, 2014, D4D was issued (i) 714,286 shares of the Issuer, and (ii) a warrant exercisable within sixty (60) days for the purchase of an additional 714,286 shares of the Issuer (collectively, the “Bridge Loan Shares”). As of December 1, 2014, D4D LLC transferred 100% of its legal and beneficial interest in the Bridge Loan Shares to its members in reliance on Rule 144.

On February 24, 2014, D4D entered into a number of agreements to consummate a bridge loan in the Issuer and SDP, which included, among other documents, the following:

Upon the Issuer’s IPO, consummated May 29, 2014, the balance of the Convertible Note automatically converted into (i) shares of the Issuer’s common stock at 70% of the per share price in the IPO, which resulted in the issuance of 714,286 shares to D4D (the “Conversion Shares”), and (ii) the Warrant, which enables D4D the option to purchase a number of additional shares of the Issuer’s common stock equal to the number of Conversion Shares (the “Warrant Shares”). While both the Conversion Shares and the Warrant Shares were initially restricted, and were not subject to resale without registration or an exemption from registration, following D4D’s transfer of the Bridge Loan Shares to its member’s on December 1, 2014, the Conversion Shares and warrants (issued by dividing the rights to purchase the Issuer’s Common Stock represented by the Warrant) transferred to the members of D4D were issued without restrictive legends pursuant to Rule 144. Following the Distribution, D4D no longer owns any shares of Common Stock of the Issuer.

Hard 4 Holdings joins this Schedule 13D because it is the sole managing member and 50% beneficial owner of D4D. Following the Issuer’s IPO, Hard 4 Holdings shared dispositive and voting power of the Bridge Loan Shares. However, following the Distribution, Hard 4 Holdings no longer has dispositive voting power as a result of its control of D4D, and instead only has voting and dispositive power with respect to the (a) 357,143 shares of the Issuer and (b) warrant that is exercisable within sixty (60) days for 357,143 additional shares of the Issuer, transferred to Hard 4 Holdings by D4D.

Mr. Walker joins this Schedule 13D because he is the manager and 100% beneficial owner of Hard 4 Holdings, which is the sole managing member of D4D. Following the consummation of the Issuer’s IPO, Mr. Walker indirectly shared control of the voting and disposition of the Bridge Loan Shares through Hard 4 Holdings. In, addition, Mr. Walker also acquired 185,714 shares of Common Stock of the Issuer (the “Walker Shares”) on May 29, 2014 with personal funds via the Issuer’s IPO. However, following the Distribution, Mr. Walker beneficially owns only a total of 900,000 shares of the Issuer (including the shares and warrants transferred to Hard 4 Holdings by D4D pursuant to the Distribution and the Walker Shares), representing 5.10% of the Issuer’s then issued and outstanding Common Stock if the warrants transferred by D4D to its members were all exercised.

Neither the Bridge Loan Shares nor the Walker Shares were acquired (or will be acquired) using borrowed funds, and none are pledged as security against borrowed funds.

The foregoing descriptions of the Bridge Loan Documents are qualified in their entirety by reference to the full text of each such agreement.

Item 4 of the Originally Filed Schedule 13D is amended by adding the following sentence to the seventh (7^th) paragraph of Item of the Originally Filed Schedule 13D:

Following the Distribution, the aforementioned transactions were consummated.

Item 5(a) of the Originally Filed Schedule 13D is amended and restated as follows:

Upon the Issuer’s IPO, consummated May 29, 2014, D4D was issued the Bridge Loan Shares. As of December 1, 2014, D4D LLC transferred 100% of its legal and beneficial interest in the Bridge Loan Shares to its members in reliance on Rule 144. As a result, D4D no longer holds any interest in any Common Stock of the Issuer.

Hard 4 Holdings joins this Schedule 13D because it is the sole managing member and 50% beneficial owner of D4D. Following the Issuer’s IPO, Hard 4 Holdings shared dispositive and voting power of the Bridge Loan Shares. However, following the Distribution, Hard 4 Holdings no longer has dispositive voting power as a result of its control of D4D, and instead only has voting and dispostive power with respect to the (a) 357,143 shares of the Issuer and (b) warrant that is exercisable within sixty (60) days for 357,143 additional shares of the Issuer, transferred to Hard 4 Holdings by D4D.

Mr. Walker joins this Schedule 13D because he is the manager and 100% beneficial owner of Hard 4 Holdings, which is the sole managing member of D4D. Following the consummation of the Issuer’s IPO, Mr. Walker indirectly shared control of the voting and disposition of the Bridge Loan Shares through Hard 4 Holdings. In, addition, Mr. Walker

also acquired 185,714 shares of Common Stock of the Issuer (the “Walker Shares”) on May 29, 2014 with personal funds via the Issuer’s IPO. Following the Distribution, Mr. Walker beneficially owns only a total of 900,000 shares of the Issuer (including the shares and warrants transferred to Hard 4 Holdings by D4D pursuant to the Distribution and the Walker Shares), representing 5.10% of the Issuer’s then issued and outstanding Common Stock if the warrants transferred by D4D to its members were all exercised.

Item 5(b) of the Originally Filed Schedule 13D is amended and restated as follows:

As of December 1, 2014, D4D LLC transferred 100% of its legal and beneficial interest in the Bridge Loan Shares to its members in reliance on Rule 144. As a result, D4D no longer holds any interest in any Common Stock of the Issuer. Hard 4 Holdings only has voting and dispositive power with respect to the (a) 357,143 shares of the Issuer and (b) warrant that is exercisable within sixty (60) days for 357,143 additional shares of the Issuer, transferred to Hard 4 Holdings by D4D. The Common Stock beneficially over which Hard 4 Holdings shares dispositive and voting power representing 4.04% of the Issuer’s then issued and outstanding Common Stock if the warrants transferred by D4D to its members were all exercised. Following the Distribution, Mr. Walker beneficially owns only a total of 900,000 shares of the Issuer (including the shares and warrants transferred to Hard 4 Holdings by D4D pursuant to the Distribution and the Walker Shares), representing 5.10% of the Issuer’s then issued and outstanding Common Stock if the warrants transferred by D4D to its members were all exercised.

Item 5(c) of the Originally Filed Schedule 13D is amended and restated as follows:

Except for the transactions contemplated by the Distribution disclosed above, the Reporting Persons have not effected any other transactions in the Issuer’s securities, including its shares of Common Stock, within sixty (60) days preceding the date hereof.

Not amended.

Item 5(e) of the Originally Filed Schedule 13D is amended by deleting the words “Not applicable” and adding the following paragraph:

As of December 1, 2014, D4D ceased to be a 5% owner of the Issuer by transferring 100% of its beneficial and legal interest in the Bridge Loan Shares to its members in accordance with the Distribution. In addition, as of December 1, 2014, Hard 4 Holdings, LLC ceased to be a 5.10% owner of the Issuer because, following the Distribution, Hard 4 Holdings would hold 4.04% of the outstanding and issued shares of Common Stock of the Company

assuming the exercise of the warrants transferred by D4D to its members. Mr. Walker continues to own exactly 5.10% of the outstanding and issued shares of Common Stock of the Company assuming the exercise of the warrants transferred by D4D to its members as of the date hereof.

Item 6 of the Originally Filed Schedule 13D is amended by deleting paragraph 4 of Item 6 and replacing it with the following:

After reasonable inquiry, and to the best of the undersigned’s knowledge and belief, the undersigned certifies that the information set forth in this Amendment No. 1 to Schedule 13D is true, complete and correct.

Date: January 2, 2015

Attention: Intentional misstatements or

omissions of fact constitute Federal

criminal violations (See 18 U.S.C. § 1001).

[Signature Page to Amendment No. 1 to Schedule 13D]

INDEX OF EXHIBITS

EXHIBIT 1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) promulgated under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them Amendment No. 1 to Schedule 13D (including amendments thereto) with regard to the common stock of Superior Drilling Products, Inc. and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filing.

In evidence thereof, the undersigned, being duly authorized, hereby execute this Joint Filing Agreement as of January 2, 2015.

[Signature Page to Joint Filing Agreement]