X0206 3/A 2014-10-16 2014-10-16 0 0001608249 Zayo Group Holdings, Inc. ZAYO 0001359354 M/C VENTURE PARTNERS VI L P C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001305476 M/C Venture Investors LLC C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001297712 M/C Venture Partners V, L.P. C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001305228 Chestnut Venture Partners LP C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001622354 M/C VP VI, L.P. C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001622210 M/C Venture Partners, LLC C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001297713 M/C VP V, LLC C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001305169 Chestnut Street Partners Inc C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 0001633221 Corelink Data Centers, LLC C/O M/C PARTNERS 75 STATE STREET, SUITE 2500 BOSTON MA 02109 0 0 1 0 Common Stock 25437645 I See Footnotes Common Stock 174870 I See Footnotes Consists of (i) 24,160,854 shares held of record by M/C Venture Partners VI, L.P.; (ii) 757,871 shares held of record by M/C Venture Investors L.L.C.; (iii) 497,320 shares held of record by M/C Venture Partners V, L.P.; and (iv) 21,600 shares held of record by Chestnut Venture Partners, L.P. (together, the "M/C Shareholders"). M/C VP VI, L.P. is the sole general partner of M/C Venture Partners VI, L.P. and M/C Venture Partners, LLC is the sole general partner of M/C VP VI, L.P. M/C VP V LLC is the sole general partner of M/C Venture Partners V, L.P. (continued) (continued from footnote 1) Chestnut Street Partners, Inc. is the sole general partner of Chestnut Venture Partners, L.P. As the Managers of M/C Venture Partners, LLC, M/C Venture Investors L.L.C. and M/C VP V LLC, Gillis S. Cashman, Brian M. Clark, David D. Croll, James F. Wade and John W. Watkins collectively have direct or indirect investment and voting authority over the securities held by M/C Venture Partners VI, L.P., M/C Venture Investors L.L.C. and M/C Venture Partners V, L.P. David D. Croll and James F. Wade collectively have investment and voting authority over the securities held by Chestnut Venture Partners, L.P. Each of the foregoing entities and individuals disclaims beneficial ownership of the shares held of record by the M/C Shareholders, except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for purposes of Section 16 or for any other purpose. The original Form 3 filed by M/C Venture Partners VI, L.P., M/C Venture Partners, LLC, M/C VP VI, L.P., M/C Venture Investors L.L.C., M/C Venture Partners V, L.P., M/C VP V LLC, Chestnut Venture Partners, L.P and Chestnut Street Partners, Inc. inadvertently omitted holdings by Corelink Data Centers, LLC. M/C Venture Partners VI, L.P., M/C VP VI, L.P. and M/C Venture Partners, LLC may be deemed to share beneficial ownership with respect to the shares held by Corelink Data Centers, LLC. M/C Venture Partners VI, L.P. is the managing member of Corelink Data Centers, LLC. M/C VP VI, L.P. is the sole general partner of M/C Venture Partners VI, L.P. and M/C Venture Partners, LLC is the sole general partner of M/C VP VI, L.P. (continued) (continued from footnote 3) As the Managers of M/C Venture Partners, LLC, Gillis S. Cashman, Brian M. Clark, David D. Croll, James F. Wade and John W. Watkins collectively have direct or indirect investment and voting authority over the securities held by Corelink Data Centers, LLC. Each of the foregoing entities and individuals disclaims beneficial ownership of the shares held of record by Corelink Data Centers, LLC. M/C VENTURE PARTNERS VI, L.P., By: M/C VP VI, L.P., its general partner, By: M/C Venture Partners, LLC, its general partner, By: /s/ Gillis S. Cashman, Manager 2015-02-10 M/C VENTURE INVESTORS L.L.C., By: /s/ Gillis S. Cashman, Manager 2015-02-10 M/C VENTURE PARTNERS V, L.P., By: M/C VP V LLC, its general partner, By: /s/ Gillis S. Cashman, Manager 2015-02-10 CHESTNUT VENTURE PARTNERS, L.P., By: Chestnut Street Partners, Inc., its general partner, By: /s/ David D. Croll, President 2015-02-10 M/C VP VI, L.P., By: M/C Venture Partners, LLC, its general partner, By: /s/ Gillis S. Cashman, Manager 2015-02-10 M/C VENTURE PARTNERS, LLC, By: /s/ Gillis S. Cashman, Manager 2015-02-10 M/C VP V LLC, By: /s/ Gillis S. Cashman, Manager 2015-02-10 CHESTNUT STREET PARTNERS, INC., By: /s/ David D. Croll, President 2015-02-10 CORELINK DATA CENTERS, LLC, By: M/C Venture Partners VI, L.P., its managing member, By: M/C VP VI, L.P., its general partner, By: M/C Venture Partners, LLC, its general partner, By: /s/ Gillis S. Cashman, Manager 2015-02-10