Filing Details

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No.1)* Opgen, Inc. (Name of Issuer) Common Shares (Title of Class of Securities) 68373L109 (CUSIP Number) December 31, 2016 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: [_] Rule 13d-1(b) [X] Rule 13d-1(c) [_] Rule 13d-1(d) __________ *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page. The information required in 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). ? CUSIP No. 68373L109

1. NAME OF REPORTING PERSONSSabby Healthcare Master Fund, Ltd.2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) [_] (b) [X] 3. SEC USE ONLY4. CITIZENSHIP OR PLACE OF ORGANIZATIONCayman IslandsNUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH 5. SOLE VOTING POWER06. SHARED VOTING POWER 1,083,6867. SOLE DISPOSITIVE POWER08. SHARED DISPOSITIVE POWER 1,083,6869. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,083,68610. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) [_]11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)4.9912. TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO? CUSIP No. 68373L1091. NAME OF REPORTING PERSONSSabby Volatility Warrant Master Fund, Ltd.2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) [_] (b) [X] 3. SEC USE ONLY4. CITIZENSHIP OR PLACE OF ORGANIZATIONCayman IslandsNUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH 5. SOLE VOTING POWER6. SHARED VOTING POWER 558,5407. SOLE DISPOSITIVE POWER08. SHARED DISPOSITIVE POWER 558,5409. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 558,54010. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) [_]11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)2.5712. TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO? CUSIP No. 68373L1091. NAME OF REPORTING PERSONSSabby Management, LLC2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) [_] (b) [X] 3. SEC USE ONLY4. CITIZENSHIP OR PLACE OF ORGANIZATIONDelaware, USANUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH 5. SOLE VOTING POWER06. SHARED VOTING POWER 1,083,6867. SOLE DISPOSITIVE POWER08. SHARED DISPOSITIVE POWER 1,083,6869. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,083,68610. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) [_]11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)12. TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) OO CUSIP No. 68373L1091. NAME OF REPORTING PERSONSHal Mintz2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS) (a) [_] (b) [X] 3. SEC USE ONLY4. CITIZENSHIP OR PLACE OF ORGANIZATIONUSANUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH 5. SOLE VOTING POWER06. SHARED VOTING POWER 1,083,6867. SOLE DISPOSITIVE POWER08. SHARED DISPOSITIVE POWER 1,083,6869. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,083,68610. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS) [_]11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)4.9912. TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) IN? CUSIP No. 68373L109 Item 1. (a). Name of Issuer:Opgen, Inc. (b). Address of issuer's principal executive offices:708 Quince Orchard Road, Suite 160 Gaithersburg, MD 20878 Item 2. (a). Name of person filing:Sabby Healthcare Master Fund, Ltd. Sabby Volatility Warrant Master Fund, Ltd. Sabby Management, LLC Hal MintzSabby Healthcare Master Fund, Ltd. c/o Ogier Fiduciary Services (Cayman) Limited 89 Nexus Way, Camana Bay Grand Cayman KY1-9007 Cayman Islands Sabby Volatility Warrant Master Fund, Ltd. c/o Ogier Fiduciary Services (Cayman) Limited 89 Nexus Way, Camana Bay Grand Cayman KY1-9007 Cayman Islands Sabby Management, LLC 10 Mountainview Road, Suite 205 Upper Saddle River, New Jersey 07458 Hal Mintz c/o Sabby Management, LLC 10 Mountainview Road, Suite 205 Upper Saddle River, New Jersey 07458(c). Citizenship:Sabby Healthcare Master Fund, Ltd. - Cayman Islands Sabby Volatility Warrant Master Fund, Ltd. - Cayman Islands Sabby Management, LLC - Delaware, USA Hal Mintz - USA(d). Title of class of securities:Common stock (e). CUSIP No.:68373L109 Item 3. If This Statement is filed pursuant to Section 240.13d-1(b) or 240.13d-2(b), or (c), check whether the person filing is a (a) [_] Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o). (b) [_] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c). (c) [_] Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c). (d) [_] Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8). (e) [_] An investment adviser in accordance with Section 240.13d-1(b)(1)(ii)(E); (f) [_] An employee benefit plan or endowment fund in accordance with Section 240.13d- 1(b)(1)(ii)(F); (g) [_] A parent holding company or control person in accordance with Section 240.13d- 1(b)(1)(ii)(G); (h) [_] A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C.1813); (i) [_] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3); (j) [_] A non-U.S. institution in accordance with Section 240.13d-1(b)(1)(ii)(J); (k) [_] Group, in accordance with Section 240.13d-1(b)(1)(ii)(K). If filing as a non-U.S. institution in accordance with Section 240.13d-1(b)(1)(ii)(J), please specify the type of institution:( (c) Number of shares as to which the person has: Sabby Healthcare Master Fund, Ltd. ( (i) Sole power to vote or to direct the vote 0 ,( (ii) Shared power to vote or to direct the vote 1,083,686 ,( (iii) Sole power to dispose or to direct the disposition of 0 ,( (iv) Shared power to dispose or to direct the disposition of 1,083,686 .Sabby Volatility Warrant Master Fund, Ltd. ( (i) Sole power to vote or to direct the vote 0 ,( (ii) Shared power to vote or to direct the vote 558,540 ,( (iii) Sole power to dispose or to direct the disposition of 0 ,( (iv) Shared power to dispose or to direct the disposition of 558,540 .Sabby Management, LLC (i) Sole power to vote or to direct the vote 0 ,( (ii) Shared power to vote or to direct the vote 1,083,686 ,( (iii) Sole power to dispose or to direct the disposition of 0 ,( (iv) Shared power to dispose or to direct the disposition of 1,083,686 .Hal Mintz ( (i) Sole power to vote or to direct the vote 0 ,( (ii) Shared power to vote or to direct the vote 1,083,686 ,( (iv) Shared power to dispose or to direct the disposition of 1,083,686 .As calculated in accordance with Rule 13d-3 of the Securities Exchange Act of 1934, as amended, (i) Sabby Healthcare Master Fund, Ltd. and Sabby Volatility Master Fund, Ltd. beneficially own 1,083,686 and 558,540 shares of the Issuer's common stock (common shares), respectively, representing approximately 4.99% and 2.57% of the Common Stock, respectively, and (ii) Sabby Management, LLC and Hal Mintz each beneficially own 1,083,686 shares of the common shares, representing approximately 4.99% of the common shares. Sabby Management, LLC and Hal Mintz do not directly own any common shares, but each indirectly owns 1,083,686 common shares. Sabby Management, LLC, a Delaware limited liability company, indirectly owns 1,083,686 common shares because it serves as the investment manager of Sabby Healthcare Master Fund, Ltd. and Sabby Volatility Warrant Master Fund, Ltd., Cayman Islands companies. Mr. Mintz indirectly owns 1,083,686 common shares in his capacity as manager of Sabby Management, LLC. Item 5. Ownership of Five Percent or Less of a Class. If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following [X].Not applicable Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.Not applicable Item 8. Identification and Classification of Members of the Group.Not applicable Item 9. Notice of Dissolution of Group.Not applicable ? Item 10. Certification.By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect. ? SIGNATURE 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. January 10, 2017 (Date)Sabby Healthcare Master Fund, Ltd. By: /s/ Harry Thompson Name: Harry Thompson Title: Authorized Person of TDF Management Ltd., a Director Sabby Volatility Warrant Master Fund, Ltd. By: /s/ Harry Thompson Name: Harry Thompson Title: Authorized Person of TDF Management Ltd., a Director Sabby Management, LLC* By: /s/ Robert Grundstein Name: Robert Grundstein Title: Chief Operating Officer/s/ Hal Mintz Hal Mintz