Exhibit 4

SUBSCRIPTION AGREEMENT

THIS INVESTMENT INVOLVES A HIGH DEGREE OF RISK. THIS INVESTMENT IS SUITABLE ONLY FOR PERSONS WHO CAN BEAR THE ECONOMIC RISK FOR AN INDEFINITE PERIOD OF TIME AND WHO CAN AFFORD TO LOSE THEIR ENTIRE INVESTMENT. FURTHERMORE, INVESTORS MUST UNDERSTAND THAT SUCH INVESTMENT IS ILLIQUID AND IS EXPECTED TO CONTINUE TO BE ILLIQUID FOR AN INDEFINITE PERIOD OF TIME. NO PUBLIC MARKET EXISTS FOR THE SECURITIES, AND NO PUBLIC MARKET IS EXPECTED TO DEVELOP FOLLOWING THIS OFFERING.

THE SECURITIES OFFERED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES OR BLUE SKY LAWS AND ARE BEING OFFERED AND SOLD IN RELIANCE ON EXEMPTIONS FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND STATE SECURITIES OR BLUE SKY LAWS. ALTHOUGH AN OFFERING STATEMENT HAS BEEN FILED WITH THE SECURITIES AND EXCHANGE COMMISSION (THE “SEC”), THAT OFFERING STATEMENT DOES NOT INCLUDE THE SAME INFORMATION THAT WOULD BE INCLUDED IN A REGISTRATION STATEMENT UNDER THE SECURITIES ACT. THE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE SEC, ANY STATE SECURITIES COMMISSION OR OTHER REGULATORY AUTHORITY, NOR HAVE ANY OF THE FOREGOING AUTHORITIES PASSED UPON THE MERITS OF THIS OFFERING OR THE ADEQUACY OR ACCURACY OF THE SUBSCRIPTION AGREEMENT OR ANY OTHER MATERIALS OR INFORMATION MADE AVAILABLE TO SUBSCRIBER IN CONNECTION WITH THIS OFFERING OVER THE WEB-BASED PLATFORM MAINTAINED BY NOVATION SOLUTIONS INC. (DBA DEALMAKER) (THE “PLATFORM”) OR THROUGH DEALMAKER SECURITIES, LLC (THE “BROKER”). ANY REPRESENTATION TO THE CONTRARY IS UNLAWFUL.

INVESTORS WHO ARE NOT “ACCREDITED INVESTORS” (AS THAT TERM IS DEFINED IN SECTION 501 OF REGULATION D PROMULGATED UNDER THE SECURITIES ACT) ARE SUBJECT TO LIMITATIONS ON THE AMOUNT THEY MAY INVEST, AS SET OUT IN SECTION 4. THE COMPANY IS RELYING ON THE REPRESENTATIONS AND WARRANTIES SET FORTH BY EACH SUBSCRIBER IN THIS SUBSCRIPTION AGREEMENT AND THE OTHER INFORMATION PROVIDED BY SUBSCRIBER IN CONNECTION WITH THIS OFFERING TO DETERMINE THE APPLICABILITY TO THIS OFFERING OF EXEMPTIONS FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT.

THE OFFERING MATERIALS MAY CONTAIN FORWARD-LOOKING STATEMENTS AND INFORMATION RELATING TO, AMONG OTHER THINGS, THE COMPANY, ITS BUSINESS PLAN AND STRATEGY, AND ITS INDUSTRY. THESE FORWARD-LOOKING STATEMENTS ARE BASED ON THE BELIEFS OF, ASSUMPTIONS MADE BY, AND INFORMATION CURRENTLY AVAILABLE TO THE COMPANY’S MANAGEMENT. WHEN USED IN THE OFFERING MATERIALS, THE WORDS “ESTIMATE,” “PROJECT,” “BELIEVE,” “ANTICIPATE,” “INTEND,” “EXPECT” AND SIMILAR EXPRESSIONS ARE INTENDED TO IDENTIFY FORWARD-LOOKING STATEMENTS, WHICH CONSTITUTE FORWARD LOOKING STATEMENTS. THESE STATEMENTS REFLECT MANAGEMENT’S CURRENT VIEWS WITH RESPECT TO FUTURE EVENTS AND ARE SUBJECT TO RISKS AND UNCERTAINTIES THAT COULD CAUSE THE COMPANY’S ACTUAL RESULTS TO DIFFER MATERIALLY FROM THOSE CONTAINED IN THE FORWARD-LOOKING STATEMENTS. INVESTORS ARE CAUTIONED NOT TO PLACE UNDUE RELIANCE ON THESE FORWARD-LOOKING STATEMENTS, WHICH SPEAK ONLY AS OF THE DATE ON WHICH THEY ARE MADE. THE COMPANY DOES NOT UNDERTAKE ANY OBLIGATION TO REVISE OR UPDATE THESE FORWARD-LOOKING STATEMENTS TO REFLECT EVENTS OR CIRCUMSTANCES AFTER SUCH DATE OR TO REFLECT THE OCCURRENCE OF UNANTICIPATED EVENTS.

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THE COMPANY MAY NOT BE OFFERING THE SECURITIES IN EVERY STATE. THE OFFERING MATERIALS DO NOT CONSTITUTE AN OFFER OR SOLICITATION IN ANY STATE OR JURISDICTION IN WHICH THE SECURITIES ARE NOT BEING OFFERED.

THE COMPANY RESERVES THE RIGHT IN ITS SOLE DISCRETION AND FOR ANY REASON WHATSOEVER TO MODIFY, AMEND AND/OR WITHDRAW ALL OR A PORTION OF THE OFFERING AND/OR ACCEPT OR REJECT IN WHOLE OR IN PART ANY PROSPECTIVE INVESTMENT IN THE SECURITIES OR TO ALLOT TO ANY PROSPECTIVE INVESTOR LESS THAN THE AMOUNT OF SECURITIES SUCH INVESTOR DESIRES TO PURCHASE. EXCEPT AS OTHERWISE INDICATED, THE OFFERING MATERIALS SPEAK AS OF THEIR DATE. NEITHER THE DELIVERY NOR THE PURCHASE OF THE SECURITIES SHALL, UNDER ANY CIRCUMSTANCES, CREATE ANY IMPLICATION THAT THERE HAS BEEN NO CHANGE IN THE AFFAIRS OF THE COMPANY SINCE THAT DATE.

PURSUANT TO SECTION 7 HEREOF, THE SECURITIES ARE SUBJECT TO AN IRREVOCABLE VOTING PROXY AND POWER OF ATTORNEY AND BY ACCEPTING ANY INTEREST IN SUCH SECURITIES THE PERSON ACCEPTING SUCH INTEREST SHALL BE DEEMED TO AGREE TO AND SHALL BECOME BOUND BY THAT IRREVOCABLE VOTING PROXY.

TO:	LiquidPiston, Inc.
	1292a Blue Hills Avenue
	Bloomfield, CT 06002

Ladies and Gentlemen:

1. Subscription.

(a) The undersigned (“Subscriber”) hereby irrevocably subscribes for and agrees to purchase the Common Stock (the “Securities”), of LiquidPiston, Inc, a Delaware corporation (the “Company”), at a purchase price of $10.00 per share (the “Per Security Price”), upon the terms and conditions set forth herein. The minimum subscription is $1,000. The rights of the Common Stock are as set forth in the Amended and Restated Certificate of Incorporation filed as an exhibit to the Offering Statement of the Company filed with the SEC (the “Offering Statement”).

(b) Subscriber understands that the Company will assess an investor fee equal to $30 plus 2.5% of the value of the shares subscribed for. This investor fee shall count against the per investor limit set out in Section 4(d)(ii) below.

(c) Subscriber understands that the Securities are being offered pursuant to an offering circular dated [DATE] (the “Offering Circular”) filed with the SEC as part of the Offering Statement. By subscribing to the Offering, Subscriber acknowledges that Subscriber has received this Subscription Agreement, copies of the Offering Circular and Offering Statement including exhibits thereto and any other information required by the Subscriber to make an investment decision.

(d) The Subscriber’s subscription may be accepted or rejected in whole or in part, at any time prior to a Closing Date (as hereinafter defined), by the Company at its sole discretion. Upon the expiration of the period specified in Subscriber’s state of residence for notice filings before sales may be made in such state, if any, the subscription may no longer be revoked at the option of the Subscriber. In addition, the Company, at its sole discretion, may allocate to Subscriber only a portion of the number of Securities Subscriber has subscribed for. The Company will notify Subscriber whether this subscription is accepted (whether in whole or in part) or rejected. If Subscriber’s subscription is rejected, Subscriber’s payment (or portion thereof if partially rejected) will be returned to Subscriber without interest and all of Subscriber’s obligations hereunder shall terminate.

(e) The aggregate number of Securities sold shall not exceed 3,000,000 shares of Common Stock (the “Maximum Offering”),  750,000 of which are being sold by certain of the Company’s existing stockholders (collectively, the “Selling Stockholders”). There is no minimum required offering amount and the Company may accept subscriptions until the termination of the Offering in accordance with its terms (the “Termination Date”). The Company may elect at any time to close all or any portion of this offering, on various dates at or prior to the Termination Date (each a “Closing Date”).

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(f) In the event of rejection of this subscription in its entirety, or in the event the sale of the Securities (or any portion thereof) is not consummated for any reason, this Subscription Agreement shall have no force or effect, except for Section 5 hereof, which shall remain in force and effect.

(g) The terms of this Subscription Agreement shall be binding upon Subscriber and its transferees, heirs, successors and assigns (collectively, “Transferees”); provided that for any such transfer to be deemed effective, the Transferee shall have executed and delivered to the Company in advance an instrument in a form acceptable to the Company in its sole discretion, pursuant to which the proposed Transferee shall acknowledge, agree, and be bound by the representations and warranties of Subscriber and the terms of this Subscription Agreement, including the Market Stand-Off in Section 6 and the Proxy in Section 7, in substantially the form set forth in Sections 6 and 7, respectively. The Company shall not record any transfer of Securities on its books unless and until such Transferee shall have complied with the terms of this Section 1(g).

2. Purchase Procedure.

(a) Payment. The purchase price for the Securities shall be paid simultaneously with the Subscriber’s subscribing to the Offering. Subscriber shall deliver a signed copy of this Subscription Agreement, along with payment for the aggregate purchase price of the Securities, by wire transfer or ACH electronic transfer or to an account designated by the Company, by credit or debit card, or by any combination of such methods with credit cards accepted up to $5,000.

(b) Subscription Procedure. Payment for the Securities shall be received by the Platform from the undersigned by wire transfer, credit or debit card, or ACH electronic transfer or other means approved by the Company at least two days prior to the applicable Closing Date, in the amount as set forth on the signature page hereto. Upon such Closing Date, the Platform shall release such funds to the Company and the Selling Stockholders. The undersigned shall receive notice and evidence of the digital entry of the number of the Securities owned by undersigned reflected on the books and records of the Company and verified by KoreTransfer Integral Transfer Agency USA Inc. (the “Transfer Agent”), which books and records shall bear a notation that the Securities were sold in reliance upon Regulation A.

3. Representations and Warranties of the Company.

The Company represents and warrants to Subscriber that the following representations and warranties are true and complete in all material respects as of the date of each Closing Date, except as otherwise indicated. For purposes of this Subscription Agreement, an individual shall be deemed to have “knowledge” of a particular fact or other matter if such individual is actually aware of such fact. The Company will be deemed to have “knowledge” of a particular fact or other matter if one of the Company’s current officers has, or at any time had, actual knowledge of such fact or other matter.

(a) Organization and standing. The Company is a corporation duly formed, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite power and authority to own and operate its properties and assets, to execute and deliver this Subscription Agreement, and any other agreements or instruments required hereunder. The Company is duly qualified and is authorized to do business and is in good standing as a foreign corporation in all jurisdictions in which the nature of its activities and of its properties (both owned and leased) makes such qualification necessary, except for those jurisdictions in which failure to do so would not have a material adverse effect on the Company or its business.

(b) Issuance of the Securities. The issuance, sale and delivery of the Securities in accordance with this Subscription Agreement has been duly authorized by all necessary corporate action on the part of the Company. The Securities, when so issued, sold and delivered against payment therefor in accordance with the provisions of this Subscription Agreement, will be duly and validly issued, fully paid and non-assessable.

(c) Authority for Agreement. The acceptance by the Company of this Subscription Agreement, and the consummation of the transactions contemplated hereby (including the issuance, sale and delivery of the Securities) are within the Company’s powers and have been duly authorized by all necessary corporate action on the part of the Company. Upon the Company’s acceptance of this Subscription Agreement, this Subscription Agreement shall constitute a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms, except (i) as limited by applicable bankruptcy, insolvency, reorganization, moratorium, and other laws of general application affecting enforcement of creditors’ rights generally, (ii) as limited by laws relating to the availability of specific performance, injunctive relief, or other equitable remedies and (iii) with respect to provisions relating to indemnification and contribution, as limited by considerations of public policy and by federal or state securities laws.

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(d) No filings. Assuming the accuracy of the Subscriber’s representations and warranties set forth in Section 4 hereof, no order, license, consent, authorization or approval of, or exemption by, or action by or in respect of, or notice to, or filing or registration with, any governmental body, agency or official is required by or with respect to the Company in connection with the subscription, delivery and performance by the Company of this Subscription Agreement except (i) for such filings as may be required under Regulation A or under any applicable state securities laws, (ii) for such other filings and approvals as have been made or obtained, or (iii) where the failure to obtain any such order, license, consent, authorization, approval or exemption or give any such notice or make any filing or registration would not have a material adverse effect on the ability of the Company to perform its obligations hereunder.

(e) Capitalization. The authorized and outstanding securities of the Company immediately prior to the initial investment in the Securities is as set forth under “Securities Being Offered” in the Offering Circular. Except as set forth in the Offering Circular, as of the date of the Offering Circular, there are no outstanding options, warrants, rights (including conversion or preemptive rights and rights of first refusal), or agreements of any kind (oral or written) for the purchase or acquisition from the Company of any of its securities.

(f) Financial statements. Complete copies of the Company’s financial statements consisting of the balance sheets of the Company as at December 31, 2021 and December 31, 2020 and the related statements of income, stockholders’ equity and cash flows for the years ended December 31, 2021 and December 31, 2020 (the “Financial Statements”) have been made available to the Subscriber and appear in the Offering Circular. The Financial Statements are based on the books and records of the Company and fairly present in all material respects the financial condition of the Company as of the respective dates they were prepared and the results of the operations and cash flows of the Company for the periods indicated. Bennett & Company, PC, which has audited the Financial Statements, is an independent accounting firm within the rules and regulations adopted by the SEC.

(g) Proceeds. The Company shall use the proceeds from the issuance and sale of the Securities as set forth in “Use of Proceeds to Issuer” in the Offering Circular.

(h) Litigation. Except as set forth in the Offering Circular, there is no pending action, suit, proceeding, arbitration, mediation, complaint, claim, charge or investigation before any court, arbitrator, mediator or governmental body, or to the Company’s knowledge, currently threatened in writing (a) against the Company or (b) against any consultant, officer, manager, director or key employee of the Company arising out of his or her consulting, employment or board relationship with the Company or that could otherwise materially impact the Company.

(i)           With respect to the Selling Stockholders and the Securities being sold by them to the Subscriber, to the Company’s knowledge:

(i) Title to the Securities. Each Selling Stockholder is the lawful owner of the Securities being offered for sale in the Offering by such Selling Stockholder, with good and marketable title thereto, and the Selling Stockholder has the absolute right to sell, assign, convey, transfer and deliver such Securities and any and all rights and benefits incident to the ownership thereof, all of which rights and benefits are transferable by the Selling Stockholder to the Subscriber, free and clear of all the following (collectively called “Claims”) of any nature whatsoever: security interests, liens, pledges, claims (pending or threatened), charges, escrows, encumbrances, lock-up arrangements, options, rights of first offer or refusal, community property rights, mortgages, indentures, security agreements or other agreements, arrangements, contracts, commitments, understandings or obligations, whether written or oral and whether or not relating in any way to credit or the borrowing of money. Delivery to the Subscriber of such Securities, upon payment therefor, will (i) pass good and marketable title to such Securities to the relevant Investor(s), free and clear of all Claims, and (ii) convey, free and clear of all Claims, any and all rights and benefits incident to the ownership of such Securities.

(ii) No Filings. No order, license, consent, authorization or approval of, or exemption by, or action by or in respect of, or notice to, or filing or registration with, any governmental body, agency or official is required by or with respect to each Selling Stockholder in connection with the sale and delivery of the Securities of such Selling Stockholder being sold hereunder, except (a) for such filings as may be required under Regulation A of the Securities Act of 1933, as amended the “Securities Act”), or under any applicable state securities laws, (b) for such other filings and approvals as have been made or obtained, or (c) where the failure to obtain any such order, license, consent, authorization, approval or exemption or give any such notice or make any filing or registration would not have a material adverse effect on the ability of the Selling Stockholder to perform its obligations under the transactions contemplated hereby.

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(iii) No Litigation. With respect to each Selling Stockholder, there is no action, suit, proceeding, judgment, claim or investigation pending, or to the knowledge of the Selling Stockholder, threatened against the Selling Stockholder which could reasonably be expected in any manner to challenge or seek to prevent, enjoin, alter or materially delay any of the transactions contemplated by this Subscription Agreement.

(iv) Non-Public Information. Each Selling Stockholder is not selling its Securities “on the basis of” (as defined in Rule 10b5-1 of the Exchange Act (as defined below)) any material, non-public information about the Securities or the Company.

4. Representations and Warranties of Subscriber. By subscribing to the Offering, Subscriber (and, if Subscriber is purchasing the Securities subscribed for hereby in a fiduciary capacity, the person or persons for whom Subscriber is so purchasing) represents and warrants, which representations and warranties are true and complete in all material respects as of such Subscriber’s respective Closing Date(s):

(a) Requisite Power and Authority. Such Subscriber has all necessary power and authority under all applicable provisions of law to execute and deliver this Subscription Agreement, and other agreements required hereunder and to carry out their provisions. All action on Subscriber’s part required for the lawful delivery of this Subscription Agreement and other agreements required hereunder have been or will be effectively taken prior to the Closing Date. By subscribing to the Offering, this Subscription Agreement and other agreements required hereunder will be valid and binding obligations of Subscriber, enforceable in accordance with their terms, except (a) as limited by applicable bankruptcy, insolvency, reorganization, moratorium or other laws of general application affecting enforcement of creditors’ rights and (b) as limited by general principles of equity that restrict the availability of equitable remedies.

(b) Investment Representations. Subscriber understands that the Securities have not been registered under the Securities Act of 1933. Subscriber also understands that the Securities are being offered and sold pursuant to an exemption from registration contained in the Securities Act based in part upon Subscriber’s representations contained in this Subscription Agreement.

(c) Illiquidity and Continued Economic Risk. Subscriber acknowledges and agrees that there is no ready public market for the Securities and that there is no guarantee that a market for their resale will ever exist. Subscriber must bear the economic risk of this investment indefinitely and the Company has no obligation to list the Securities on any market or take any steps (including registration under the Securities Act or the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) with respect to facilitating trading or resale of the Securities. Subscriber acknowledges that Subscriber is able to bear the economic risk of losing Subscriber’s entire investment in the Securities. Subscriber also understands that an investment in the Company involves significant risks and has taken full cognizance of and understands all of the risk factors relating to the purchase of Securities.

(d) Accredited Investor Status or Investment Limits. Subscriber represents that either:

(i) Subscriber is an “accredited investor” within the meaning of Rule 501 of Regulation D under the Securities Act; or

(ii) The purchase price set out in paragraph (b) of the signature page to this Subscription Agreement, together with any other amounts previously used to purchase Securities in this offering, does not exceed 10% of the greater of the Subscriber’s annual income or net worth.

Subscriber represents that to the extent it has any questions with respect to its status as an accredited investor, or the application of the investment limits, it has sought professional advice.

(e) Shareholder information. Within five days after receipt of a request from the Company, the Subscriber hereby agrees to provide such information with respect to its status as a shareholder (or potential shareholder) and to execute and deliver such documents as may reasonably be necessary to comply with any and all laws and regulations to which the Company is or may become subject. Subscriber further agrees that in the event it transfers any Securities, it will require the transferee of such Securities to agree to provide such information to the Company as a condition of such transfer.

(f) Company Information. Subscriber has had such opportunity as it deems necessary (which opportunity may have presented through online chat or commentary functions) to discuss the Company’s business, management and financial affairs with managers, officers and management of the Company and has had the opportunity to review the Company’s operations and facilities. Subscriber has also had the opportunity to ask questions of and receive answers from the Company and its management regarding the terms and conditions of this investment. Subscriber acknowledges that except as set forth herein, no representations or warranties have been made to Subscriber, or to Subscriber’s advisors or representative, by the Company or others with respect to the business or prospects of the Company or its financial condition.

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(g) Valuation. The Subscriber acknowledges that the price of the Securities was set by the Company on the basis of the Company’s internal valuation and no warranties are made as to value. The Subscriber further acknowledges that future offerings of Securities may be made at lower valuations, with the result that the Subscriber’s investment will bear a lower valuation.

(h) Domicile. Subscriber maintains Subscriber’s domicile (and is not a transient or temporary resident) at the address shown on the signature page.

(i) No Brokerage Fees. There are no claims for brokerage commission, finders’ fees or similar compensation in connection with the transactions contemplated by this Subscription Agreement or related documents based on any arrangement or agreement binding upon Subscriber.

(j) Foreign Investors. If Subscriber is not a United States person (as defined by Section 7701(a)(30) of the Internal Revenue Code of 1986, as amended), Subscriber hereby represents that it has satisfied itself as to the full observance of the laws of its jurisdiction in connection with any invitation to subscribe for the Securities or any use of this Subscription Agreement, including (i) the legal requirements within its jurisdiction for the purchase of the Securities, (ii) any foreign exchange restrictions applicable to such purchase, (iii) any governmental or other consents that may need to be obtained, and (iv) the income tax and other tax consequences, if any, that may be relevant to the purchase, holding, redemption, sale, or transfer of the Securities. Subscriber’s subscription and payment for and continued beneficial ownership of the Securities will not violate any applicable securities or other laws of the Subscriber’s jurisdiction.

5. Survival of Representations and Indemnity. The representations, warranties and covenants made by the Subscriber and rights and agreements set forth in Sections 6, 7 and 8 herein shall survive the Termination Date. The Subscriber agrees to indemnify and hold harmless the Company, the Selling Stockholders and their respective officers, directors and affiliates, and each other person, if any, who controls the Company or any Selling Stockholder within the meaning of Section 15 of the Securities Act against any and all loss, liability, claim, damage and expense whatsoever (including, but not limited to, any and all reasonable attorneys’ fees, including attorneys’ fees on appeal) and expenses reasonably incurred in investigating, preparing or defending against any false representation or warranty or breach of failure by the Subscriber to comply with any covenant or agreement made by the Subscriber herein or in any other document furnished by the Subscriber to any of the foregoing in connection with this transaction.

6. Lock-Up Period. To the extent requested by the Company or the managing underwriter of securities of the Company, the Subscriber hereby agrees that it will not, without the prior written consent of the managing underwriter, during the period commencing on the date of the final prospectus relating to the registration by the Company for its own behalf of shares of its Common Stock or any other equity securities under the Securities Act on a registration statement on Form S-1 in connection with the Company’s initial public offering (the “IPO”), and ending on the date specified by the Company and the managing underwriter (such period not to exceed one hundred eighty (180) days, or such other period as may be requested by the Company or an underwriter to accommodate regulatory restrictions on (1) the publication or other distribution of research reports, and (2) analyst recommendations and opinions, including, but not limited to, the restrictions contained in FINRA Rule 2241 or NYSE Rule 472(f)(4), or any successor provisions or amendments thereto), (i) lend; offer; pledge; sell; contract to sell; sell any option or contract to purchase; purchase any option or contract to sell; grant any option, right, or warrant to purchase; or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable (directly or indirectly) for Common Stock held immediately before the effective date of the registration statement for the IPO or (ii) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of such securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or other securities, in cash, or otherwise. The foregoing provisions of this Section 6 shall apply only to the IPO, shall not apply to the sale of any shares to an underwriter pursuant to an underwriting agreement, or the transfer of any shares to any trust for the direct or indirect benefit of the Subscriber or the immediate family of the Subscriber, provided that the trustee of the trust agrees to be bound in writing by the restrictions set forth herein, and provided further that any such transfer shall not involve a disposition for value, and shall be applicable to the Subscriber only if all officers and directors are subject to the same restrictions and the Company uses commercially reasonable efforts to obtain a similar agreement from all stockholders individually owning more than one percent (1%) of the Company’s outstanding Common Stock (after giving effect to conversion into Common Stock of all outstanding preferred stock). The underwriters in connection with such registration are intended third party beneficiaries of this Section 6 and shall have the right, power and authority to enforce the provisions hereof as though they were a party hereto. The Subscriber further agrees to execute such agreements as may be reasonably requested by the underwriters in connection with such registration that are consistent with this Section 6 or that are necessary to give further effect thereto. Any discretionary waiver or termination of the restrictions of any or all of such agreements by the Company or the underwriters shall apply pro rata to all Company stockholders that are subject to such agreements, based on the number of shares subject to such agreements.

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7. Voting Proxy. The Subscriber shall, and hereby does, appoint the Chief Executive Officer of the Company (the “CEO”), or his or her successor, as the Subscriber’s true and lawful proxy and attorney, with the power to act alone and with full power of substitution, to, consistent with this instrument and on behalf of the Subscriber, (i) vote all Securities held of record by Subscriber (including any shares of the Company’s capital stock that the Subscriber may acquire in the future), (ii) give and receive notices and communications, (iii) execute any written consent, instrument or document that the CEO determines is necessary or appropriate at the CEO’s complete discretion, and (iv) take all actions necessary or appropriate in the judgment of the CEO for the accomplishment of the foregoing. The proxy and power granted by the Subscriber pursuant to this Section 7 are coupled with an interest. Such proxy and power will be irrevocable. The proxy and power, so long as the Subscriber is an individual, will survive the death, incompetency and disability of the Subscriber and, so long as the Subscriber is an entity, will survive the merger or reorganization of the Subscriber or any other entity holding the Securities. Such proxy shall be binding upon the heirs, estate, executors, personal representatives, successors and assigns of the Subscriber (including any transferee of any Subscriber); any transferee receiving the Subscriber’s Securities (or any portion thereof) shall agree to be bound by the provisions of this Section 7. However, the proxy will terminate upon the closing of a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act covering the offer and sale of Common Stock or the effectiveness of a registration statement under the Exchange Act covering the Common Stock. If any provision of this proxy or any part of any this Section 7 is held under any circumstances to be invalid or unenforceable in any jurisdiction, then (a) such provision or part thereof shall, with respect to such circumstances and in such jurisdiction, be deemed amended to conform to applicable laws so as to be valid and enforceable to the fullest possible extent, (b) the invalidity or unenforceability of such provision or part thereof under such circumstances and in such jurisdiction shall not affect the validity or enforceability of such provision or part thereof under any other circumstances or in any other jurisdiction, and (c) the invalidity or unenforceability of such provision or part thereof shall not affect the validity or enforceability of the remainder of such provision or the validity or enforceability of any other provision of this proxy. Each provision of this proxy is separable from every other provision of this proxy, and each part of each provision of this proxy is separable from every other part of such provision.

8. Governing Law; Jurisdiction. This Subscription Agreement shall be governed and construed in accordance with the laws of the State of Delaware without regard to conflicts of law principles.

EACH OF THE SUBSCRIBER AND THE COMPANY CONSENTS TO THE JURISDICTION OF ANY STATE OR FEDERAL COURT OF COMPETENT JURISDICTION LOCATED WITHIN THE STATE OF DELAWARE AND NO OTHER PLACE AND IRREVOCABLY AGREES THAT ALL ACTIONS OR PROCEEDINGS RELATING TO THIS SUBSCRIPTION AGREEMENT NOT ARISING UNDER THE FEDERAL SECURITIES LAWS MAY BE LITIGATED IN SUCH COURTS. EACH OF SUBSCRIBER AND THE COMPANY ACCEPTS FOR ITSELF AND HIMSELF AND IN CONNECTION WITH ITS AND HIS RESPECTIVE PROPERTIES, GENERALLY AND UNCONDITIONALLY, THE EXCLUSIVE JURISDICTION OF THE AFORESAID COURTS AND WAIVES ANY DEFENSE OF FORUM NON CONVENIENS, AND IRREVOCABLY AGREES TO BE BOUND BY ANY JUDGMENT RENDERED THEREBY IN CONNECTION WITH THIS SUBSCRIPTION AGREEMENT NOT ARISING UNDER THE FEDERAL SECURITIES LAWS. EACH OF SUBSCRIBER AND THE COMPANY FURTHER IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS OUT OF ANY OF THE AFOREMENTIONED COURTS IN THE MANNER AND IN THE ADDRESS SPECIFIED IN SECTION 9 AND PROVIDED WITH THE EXECUTION OF THIS SUBSCRIPTION AGREEMENT.

9. Notices. Notice, requests, demands and other communications relating to this Subscription Agreement and the transactions contemplated herein shall be in writing and shall be deemed to have been duly given if and when (a) delivered personally, on the date of such delivery; or (b) mailed by registered or certified mail, postage prepaid, return receipt requested, in the third day after the posting thereof; or (c) emailed, telecopied or cabled, on the date of such delivery to the address of the respective parties as follows:

If to the Company, to: LiquidPiston, Inc. 1292a Blue Hills Avenue Bloomfield, CT 06002	with a required copy to: Goodwin Procter LLP 620 Eighth Avenue New York, NY 10018-1405 Attn: Stephen Davis, Esq. and Aaron Berman, Esq.
If to a Subscriber, to Subscriber’s address as provided with the execution of this Subscription Agreement

or to such other address as may be specified by written notice from time to time by the party entitled to receive such notice. Any notices, requests, demands or other communications by telecopy or cable shall be confirmed by letter given in accordance with (a) or (b) above.

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The Subscriber hereby agrees that the Company may deliver all notices, financial statements, valuations, reports, reviews, analyses or other materials, and any and all other documents, information and communications concerning the affairs of the Company and its investments, including, without limitation, information about the investment, required or permitted to be provided to the Subscriber under the Offering Circular or hereunder by means of e-mail or by posting on an electronic message board or by other means of electronic communication. The Subscriber hereby consents to receive electronically all documents, communications, notices, contracts, and agreements arising from or relating in any way to your or our rights, obligations or services hereunder or pursuant to your ownership of the Securities.

10. Miscellaneous.

(a) All pronouns and any variations thereof shall be deemed to refer to the masculine, feminine, neuter, singular or plural, as the identity of the person or persons or entity or entities may require.

(b) This Subscription Agreement is not transferable or assignable by Subscriber.

(c) The representations, warranties and agreements contained herein shall be deemed to be made by and be binding upon Subscriber and its heirs, executors, administrators and successors and shall inure to the benefit of the Company and its successors and assigns.

(d) None of the provisions of this Subscription Agreement may be waived, changed or terminated orally or otherwise, except as specifically set forth herein or except by a writing signed by the Company and Subscriber.

(e) In the event any part of this Subscription Agreement is found to be void or unenforceable, the remaining provisions are intended to be separable and binding with the same effect as if the void or unenforceable part were never the subject of agreement.

(f) The invalidity, illegality or unenforceability of one or more of the provisions of this Subscription Agreement in any jurisdiction shall not affect the validity, legality or enforceability of the remainder of this Subscription Agreement in such jurisdiction or the validity, legality or enforceability of this Subscription Agreement, including any such provision, in any other jurisdiction, it being intended that all rights and obligations of the parties hereunder shall be enforceable to the fullest extent permitted by law.

(g) This Subscription Agreement supersedes all prior discussions and agreements between the parties with respect to the subject matter hereof and contains the sole and entire agreement between the parties hereto with respect to the subject matter hereof.

(h) The terms and provisions of this Subscription Agreement are intended solely for the benefit of each party hereto and their respective successors and assigns, and it is not the intention of the parties to confer, and no provision hereof shall confer, third-party beneficiary rights upon any other person.

(i) The headings used in this Subscription Agreement have been inserted for convenience of reference only and do not define or limit the provisions hereof.

(j) This Subscription Agreement may be executed in any number of counterparts, including by electronic transmission, each of which will be deemed an original, but all of which together will constitute one and the same instrument.

(k) If any recapitalization or other transaction affecting the stock of the Company is effected, then any new, substituted or additional securities or other property which is distributed with respect to the Securities shall be immediately subject to this Subscription Agreement, to the same extent that the Securities, immediately prior thereto, shall have been covered by this Subscription Agreement.

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(l) No failure or delay by any party in exercising any right, power or privilege under this Subscription Agreement shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right, power or privilege. The rights and remedies herein provided shall be cumulative and not exclusive of any rights or remedies provided by law.

(m) The Subscriber acknowledges and understands that, but for the waiver made herein, the Subscriber may be entitled, upon written demand under oath stating the purpose thereof, to inspect for any proper purpose, and to make copies and extracts from, the Company’s stock ledger, a list of its stockholders, and its other books and records, and the books and records of subsidiaries of the Company, if any, under the circumstances and in the manner provided in Section 220 of the General Corporation Law of Delaware (any and all such rights, and any and all such other rights of the Subscriber as may be provided for in Section 220, the “Inspection Rights”). In light of the foregoing, until the first sale of securities of the Company to the general public pursuant to a registration statement filed with and declared effective by the Securities and Exchange Commission under the Securities Act, the Subscriber hereby unconditionally and irrevocably waives the Inspection Rights, whether such Inspection Rights would be exercised or pursued directly or indirectly pursuant to Section 220 or otherwise, and covenants and agrees never to directly or indirectly commence, voluntarily aid in any way, prosecute, assign, transfer, or cause to be commenced any claim, action, cause of action, or other proceeding to pursue or exercise the Inspection Rights. The foregoing waiver shall not affect any rights of a director, in his or her capacity as such, under Section 220.

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APPENDIX A

An accredited investor, as defined in Rule 501(a) of the Securities Act of 1933, as amended, includes the following categories of investor:

(1) Any bank as defined in section 3(a)(2) of the Securities Act, or any savings and loan association or other institution as defined in section 3(a)(5)(A) of the Securities Act whether acting in its individual or fiduciary capacity; any broker or dealer registered pursuant to section 15 of the Securities Exchange Act of 1934; any investment adviser registered pursuant to section 203 of the Investment Advisers Act of 1940 or registered pursuant to the laws of a state; any investment adviser relying on the exemption from registering with the Commission under section 203(l) or (m) of the Investment Advisers Act of 1940; any insurance company as defined in section 2(a)(13) of the Securities Act; any investment company registered under the Investment Company Act of 1940 or a business development company as defined in section 2(a)(48) of that Act; any Small Business Investment Company licensed by the U.S. Small Business Administration under section 301(c) or (d) of the Small Business Investment Act of 1958; any Rural Business Investment Company as defined in section 384A of the Consolidated Farm and Rural Development Act; any plan established and maintained by a state, its political subdivisions, or any agency or instrumentality of a state or its political subdivisions, for the benefit of its employees, if such plan has total assets in excess of $5,000,000; any employee benefit plan within the meaning of the Employee Retirement Income Security Act of 1974 if the investment decision is made by a plan fiduciary, as defined in section 3(21) of such act, which is either a bank, savings and loan association, insurance company, or registered investment adviser, or if the employee benefit plan has total assets in excess of $5,000,000 or, if a self-directed plan, with investment decisions made solely by persons that are accredited investors;

(2) Any private business development company as defined in section 202(a)(22) of the Investment Advisers Act of 1940;

(3) Any organization described in section 501(c)(3) of the Internal Revenue Code, corporation, Massachusetts or similar business trust, or partnership, or limited liability company, not formed for the specific purpose of acquiring the securities offered, with total assets in excess of $5,000,000;

(4) Any director, executive officer, or general partner of the issuer of the securities being offered or sold, or any director, executive officer, or general partner of a general partner of that issuer;

(5) Any natural person whose individual net worth, or joint net worth with that person's spouse or spousal equivalent, exceeds $1,000,000.

(i) Except as provided in paragraph (5)(ii) of this section, for purposes of calculating net worth under this paragraph (5):

(A) The person's primary residence shall not be included as an asset;

(B) Indebtedness that is secured by the person's primary residence, up to the estimated fair market value of the primary residence at the time of the sale of securities, shall not be included as a liability (except that if the amount of such indebtedness outstanding at the time of sale of securities exceeds the amount outstanding 60 days before such time, other than as a result of the acquisition of the primary residence, the amount of such excess shall be included as a liability); and

(C) Indebtedness that is secured by the person's primary residence in excess of the estimated fair market value of the primary residence at the time of the sale of securities shall be included as a liability;

(ii) Paragraph (5)(i) of this section will not apply to any calculation of a person's net worth made in connection with a purchase of securities in accordance with a right to purchase such securities, provided that:

(A) Such right was held by the person on July 20, 2010;

(B) The person qualified as an accredited investor on the basis of net worth at the time the person acquired such right; and

(C) The person held securities of the same issuer, other than such right, on July 20, 2010.

(6) Any natural person who had an individual income in excess of $200,000 in each of the two most recent years or joint income with that person's spouse or spousal equivalent in excess of $300,000 in each of those years and has a reasonable expectation of reaching the same income level in the current year;

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(7) Any trust, with total assets in excess of $5,000,000, not formed for the specific purpose of acquiring the securities offered, whose purchase is directed by a sophisticated person as described in §230.506(b)(2)(ii); 

(8) Any entity in which all of the equity owners are accredited investors;

(9) Any entity, of a type of not listed in paragraphs (1), (2), (3), (7), or (8), not formed for the specific purpose of acquiring the securities offered, owning investments in excess of $5,000,000;

(10) Any natural person holding in good standing one or more professional certifications or designations or credentials from an accredited educational institution that the Commission has designated as qualifying an individual for accredited investor status;

(11) Any natural person who is a “knowledgeable employee,” as defined in rule 3c-5(a)(4) under the Investment Company Act of 1940 (17 CFR 270.3c-5(a)(4)), of the issuer of the securities being offered or sold where the issuer would be an investment company, as defined in section 3 of such act, but for the exclusion provided by either section 3(c)(1) or section 3(c)(7) of such act;

(12) Any “family office,” as defined in rule 202(a)(11)(G)-1 under the Investment Advisers Act of 1940 (17 CFR 275.202(a)(11)(G)-1):

(i) With assets under management in excess of $5,000,000,

(ii) That is not formed for the specific purpose of acquiring the securities offered, and

(iii) Whose prospective investment is directed by a person who has such knowledge and experience in financial and business matters that such family office is capable of evaluating the merits and risks of the prospective investment; and

(13) Any “family client,” as defined in rule 202(a)(11)(G)-1 under the Investment Advisers Act of 1940 (17 CFR 275.202(a)(11)(G)-1)), of a family office meeting the requirements in paragraph (12) of this section and whose prospective investment in the issuer is directed by such family office pursuant to paragraph (12)(iii).

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