HYLN Hyliion Holdings Corp

Item 1. Security and Issuer.

This Schedule 13D (this “Schedule 13D”) relates to the common stock, par value $0.0001 per share (the “Common Stock”), of Hyliion Holdings Corp., a Delaware corporation (formerly Tortoise Acquisition Corp.) (the “Issuer”). The principal executive offices of the Issuer are located at 1202 BMC Drive, Suite 100, Cedar Park, TX 78613.

Item 2. Identity and Background.

The persons filing this statement and the persons enumerated in Instruction C of Schedule 13D and, where applicable, their respective places of organization, general partners, directors, executive officers and controlling persons and the information regarding them, are as follows:

(a)       This Schedule 13D is filed by:

·           Axioma Ventures, LLC, a Florida limited liability company (“Axioma Ventures”);

·           Axioma Holdings, LLC, a Florida limited liability company (“Axioma Holdings”);

·           Axioma Management, LLC, a Florida limited liability company (“Axioma Management”);

·           Howard M. Jenkins, a director of the Issuer;

·           Alexander H. Jenkins; and

·           Kiran Lingam.

The foregoing persons are hereinafter sometimes collectively referred to as the “Reporting Persons.” The shares of Common Stock to which this Schedule 13D relates are held of record by Axioma Ventures. The sole member of Axioma Ventures is Axioma Holdings and the managers of Axioma Ventures are Alexander Jenkins and Kiran Lingam.   The sole manager of Axioma Holdings is Axioma Management.  Howard Jenkins, Alexander Jenkins and Kiran Lingam are managers of Axioma Management.  Each of Axioma Holdings, Axioma Management, Howard Jenkins, Alexander Jenkins and Kiran Lingam therefore may be deemed to share voting and dispositive power with respect to the shares of Common Stock held of record by Axioma Ventures.  In addition, Howard M. Jenkins serves as Class II director of the Issuer, with his term expiring at the Issuer’s 2022 annual meeting of stockholders.

Item 3. Source and Amount of Funds or Other Consideration.

The consideration used to acquire beneficial ownership of the shares of Common Stock of the Issuer consisted of securities of Hyliion Inc. (“Legacy Hyliion”). The Reporting Persons acquired the shares of Common Stock pursuant to the Business Combination Agreement and Plan of Reorganization, dated as of June 18, 2020 (the “Business Combination Agreement”), by and among Tortoise Acquisition Corp. (“Tortoise”), Legacy Hyliion and SHLL Merger Sub Inc., a wholly-owned subsidiary of Tortoise (“Merger Sub”), pursuant to which Merger Sub merged (the “Merger”) with and into Legacy Hyliion, with Legacy Hyliion surviving the merger as a wholly-owned subsidiary of Tortoise (which subsequently changed its name to “Hyliion Holdings Corp.”). Axioma Ventures used working capital in order to acquire the securities of Legacy Hyliion.

Item 4. Purpose of Transaction.

The information provided in response to Items 2 and 3 hereof is incorporated herein by reference.

The Reporting Persons acquired the Common Stock for investment purposes in the Reporting Persons’ ordinary course of business. In pursuing such investment purposes, the Reporting Persons may further purchase, hold, vote, trade, dispose or otherwise deal in the Common Stock at times, and in such manner (including pursuant to hedging transactions), as they deem advisable to benefit from changes in market prices of the Common Stock, changes in the Issuer’s operations, business strategy or prospects, or from a sale or merger of the Issuer. To evaluate such alternatives, the Reporting Persons routinely will monitor the Issuer’s operations, prospects, business development, management, competitive and strategic matters, capital structure, and prevailing market conditions, as well as alternative investment opportunities, liquidity requirements of the Reporting Persons and other investment considerations. Consistent with their investment research methods and evaluation criteria, the Reporting Persons may discuss such matters with management or directors of the Issuer, other shareholders, industry analysts, existing or potential strategic partners or competitors, investment and financing professionals, sources of credit and other investors. Such factors and discussions may materially affect, and result in, the Reporting Persons’ modifying their ownership of the Common Stock, exchanging information with the Issuer pursuant to appropriate confidentiality or similar agreements, proposing changes in the Issuer’s operations, governance or capitalization, or in proposing one or more of the other actions described in paragraphs (a) through (j) of Item 4 of Schedule 13D. The Reporting Persons reserve the right to formulate other plans and/or make other proposals, and take such actions with respect to their investment in the Issuer, including any or all of the actions set forth in paragraphs (a) through (j) of Item 4 of Schedule 13D, or acquire additional shares of Common Stock or dispose of all shares of Common Stock beneficially owned by them, in the public market or privately negotiated transactions. The Reporting Persons may at any time reconsider and change their plans or proposals relating to the foregoing.

Item 5. Interest in Securities of the Issuer.

The information in Items 4 and 6 hereof is incorporated by reference herein.

Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.

The information in Items 2 and 3 is incorporated by reference herein.

In connection with the Merger, on October 1, 2020, the Issuer and certain stockholders of Legacy Hyliion, including Axioma Ventures, and executives of the Company (the “Legacy Holders”) entered into a Lock-Up Agreement (each, a “Lock-Up Agreement”). The terms of the Lock-Up Agreements provide for the Common Stock held by the Legacy Holders as of immediately after the Merger to be locked-up for a period of 180 days after the closing of the Merger, subject to certain exceptions.

In connection with the Merger, the Issuer entered into an Amended and Restated Registration Rights Agreement with several parties (the “Holders”), including Axioma Ventures, pursuant to which the Holders, subject to certain conditions, are entitled to registration rights with respect to securities of the Issuer (the “Registrable Securities”). Pursuant to this agreement, the Issuer agreed that, within 30 calendar days after the consummation of the Merger, it will file with the SEC a registration statement registering the resale of the Registrable Securities, and use its reasonable best efforts to have such registration statement declared effective by the SEC as soon as reasonably practicable after the filing thereof. Certain of the Holders were granted demand underwritten offering registration rights and all of the Holders were granted piggyback registration rights. The agreement terminates upon the earlier of (a) ten years following the Merger or (b) the date as of which the Holders cease to hold any registrable securities.

The Reporting Persons are parties to an agreement with respect to the joint filing of this Schedule 13D and any amendments hereto. A copy of such agreement is attached as Exhibit 1 to this Schedule 13D and is incorporated by reference herein.

Item 7. Material to Be Filed as Exhibits.

* Filed herewith.

SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

DATED: October 13, 2020

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