OpGen, Inc.

Exhibit 2

OpGen, Inc.

000 Xxxxxx Xxxxxxx Xxxx, Xxxxx 000

Xxxxxxxxxxxx, XX 00000

____________________, 2017

OpGen, Inc.
Telephone:	(000) 000-0000
Facsimile:	(000) 000-0000
Attention:	Xxxxxxx X. Dec, Chief Financial Officer
E-mail:	xxxx@xxxxx.xxx

Re: OpGen, Inc. - Lock-Up Agreement

Dear Madam/Sir:

This Lock-Up Agreement is being delivered to you in connection with the Securities Purchase Agreement (the “Purchase Agreement”), dated as of ___________, ___ 2017 by and among OpGen, Inc. (the “Company”) and the investors party thereto (the “Buyers”), with respect to the issuance of (i) shares of the Company’s common stock, par value $0.01 per share (the “Common Stock”) and (ii) warrants (the “Warrants”) which Warrants will be exercisable to purchase Common Stock.  Capitalized terms used herein and not otherwise defined herein shall have the respective meanings set forth in the Purchase Agreement.

In order to induce the Purchasers to enter into the Purchase Agreement, the undersigned agrees that, commencing on the date hereof and ending 90 days following the effective date of the Registration Statement on Form S-1 (File No. 333-218392) (the “Lock-Up Period”), the undersigned will not, and will cause all affiliates (as defined in Rule 144 promulgated under the Securities Act of 1933, as amended) of the undersigned or any person in privity with the undersigned or any affiliate of the undersigned with respect to the securities of the Company not to, (i) sell, offer to sell, contract or agree to sell, hypothecate, pledge, grant any option to purchase, make any short sale or otherwise dispose of or agree to dispose of, directly or indirectly, any (A) Common Stock or (B) any securities of the Company or any of its subsidiaries which would entitle the holder thereof to acquire at any time Common Stock, including, without limitation, any debt, preferred stock, right, option, warrant or other instrument that is at any time convertible into or exercisable or exchangeable for, or otherwise entitles the holder thereof to receive, Common Stock (“Common Stock Equivalents”), or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section 16 of the Securities and Exchange Act of 1934, as amended and the rules and regulations of the Securities and Exchange Commission promulgated thereunder, with respect to any Common Stock or Common Stock Equivalents owned directly by the undersigned (including holding as a custodian) or with respect to which the undersigned has beneficial ownership within the rules and regulations of the Securities and Exchange Commission (collectively, the “Undersigned's Shares”), 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 any of the Undersigned's Shares, 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, (iii) make any demand for or exercise any right or cause to be filed a registration statement, including any amendments thereto, with respect to the registration of any Common Stock or Common Stock Equivalents or (iv) publicly disclose the intention to do any of the foregoing.

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The foregoing restriction is expressly agreed to preclude the undersigned, and any affiliate of the undersigned and any person in privity with the undersigned or any affiliate of the undersigned with respect to the securities of the Company, from engaging in any hedging or other transaction which is designed to or which reasonably could be expected to lead to or result in a sale or disposition of the Undersigned's Shares even if the Undersigned's Shares would be disposed of by someone other than the undersigned.  Such prohibited hedging or other transactions would include, without limitation, any short sale or any purchase, sale or grant of any right (including, without limitation, any put or call option) with respect to any of the Undersigned's Shares or with respect to any security that includes, relates to, or derives any significant part of its value from the Undersigned's Shares.

Notwithstanding the foregoing, the undersigned may transfer the Undersigned's Shares (i) as a bona fide gift or gifts, provided that the donee or donees thereof agree to be bound in writing by the restrictions set forth herein, (ii) to any trust for the direct or indirect benefit of the undersigned or the immediate family of the undersigned, 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, or (iii) if acquired by the undersigned in open market transactions after the offering.  For purposes of this Lock-Up Agreement, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than first cousin.  The undersigned now has, and, except as contemplated by the immediately preceding sentence, for the duration of this Lock-Up Agreement will have, good and marketable title to the Undersigned's Shares, free and clear of all liens, encumbrances, and claims whatsoever.  The undersigned also agrees and consents to the entry of stop transfer instructions with the Company's transfer agent (the “Transfer Agent”) and registrar against the transfer of the Undersigned's Shares except in compliance with the foregoing restrictions.

In order to enforce this covenant, the Company shall impose irrevocable stop-transfer instructions preventing the Transfer Agent from effecting any actions in violation of this Lock-Up Agreement.

The undersigned acknowledges that the execution, delivery and performance of this Lock-Up Agreement is a material inducement to each Purchaser to complete the transactions contemplated by the Purchase Agreement and that the Company shall be entitled to specific performance of the undersigned's obligations hereunder.  The undersigned hereby represents that the undersigned has the power and authority to execute, deliver and perform this Lock-Up Agreement, that the undersigned has received adequate consideration therefor and that the undersigned will indirectly benefit from the closing of the transactions contemplated by the Purchase Agreement.

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The undersigned understands and agrees that this Lock-Up Agreement is irrevocable and shall be binding upon the undersigned's heirs, legal representatives, successors, and assigns.  This Lock-Up Agreement shall not be amended without the prior written consent of X.X. Xxxxxxxxxx & Co., LLC.

This Lock-Up Agreement may be executed in two counterparts, each of which shall be deemed an original but both of which shall be considered one and the same instrument.

This Lock-Up Agreement will be governed by and construed in accordance with the laws of the State of New York, without giving effect to any choice of law or conflicting provision or rule (whether of the State of New York, or any other jurisdiction) that would cause the laws of any jurisdiction other than the State of New York to be applied.  In furtherance of the foregoing, the internal laws of the State of New York will control the interpretation and construction of this Lock-Up Agreement, even if under such jurisdiction's choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

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Very truly yours,

______________________________

Exact Name of Stockholder

______________________________

Authorized Signature

______________________________

Title

Agreed to and Acknowledged:

OPGEN, INC.

By: _______________________

       Name:

       Title:

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