X0306 4 2018-05-09 0 0001366527 Carbon Black, Inc. CBLK 0001013713 MAEDER PAUL A C/O HIGHLAND CAPITAL PARTNERS ONE BROADWAY, 16TH FLOOR CAMBRIDGE MA 02142 1 0 0 0 Common Stock 2018-05-09 4 A 0 6007 0 A 6007 D Common Stock 4270065 I By Highland Capital Partners VI Limited Partnership Common Stock 2340874 I By Highland Capital Partners VI-B Limited Partnership Common Stock 211495 I By Highland Entrepreneurs' Fund VI Limited Partnership Common Stock 1093318 I By Highland Capital Partners VII Limited Partnership Common Stock 264931 I By Highland Capital Partners VII-B Limited Partnership Common Stock 385824 I By Highland Capital Partners VII-C Limited Partnership Common Stock 34258 I By Highland Entrepreneurs' Fund VII Limited Partnership The shares were acquired pursuant to a restricted stock unit award under the 2018 Stock Option and Incentive Plan. Each restricted stock unit represents a contingent right to receive one share of Carbon Black, Inc. common stock. The restricted stock units vest on the earlier of (i) the first anniversary of the vesting commencement date, May 9, 2019 or (ii) the next annual meeting of the Carbon Black Inc.'s shareholders, subject to a continuous service relationship through such date. The shares are held directly by Highland Capital Partners VI Limited Partnership ("Highland Capital VI"). The general partner of Highland Capital VI is Highland Management Partners VI Limited Partnership ("HMP VI LP"). The general partner of HMP VI LP is Highland Management Partners VI, Inc. ("Highland Management"). Mr. Maeder is a managing director of Highland Management. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. The shares are held directly by Highland Capital Partners VI-B Limited Partnership ("Highland Capital VI-B"). The general partner of Highland Capital VI-B is HMP VI LP. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. The shares are held directly by Highland Entrepreneurs' Fund VI Limited Partnership ("Highland VI Entrepreneurs' Fund"). The general partner of Highland VI Entrepreneurs' Fund is HEF VI Limited Partnership ("HEF"). The general partner of HEF is Highland Management. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. The shares are held directly by Highland Capital Partners VII Limited Partnership ("Highland Capital VII"). The general partner of Highland Capital VII is Highland Management Partners VII Limited Partnership ("HMP VII LP"). The general partner of HMP VII LP is Highland Management Partners VII, LLC ("HMP VII LLC"). Mr. Maeder is a managing director of HMP VII LLC. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. The shares are held directly by Highland Capital Partners VII-B Limited Partnership ("Highland Capital VII-B"). The general partner of Highland Capital VII-B is HMP VII LP. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. The shares are held directly by Highland Capital Partners VII-C Limited Partnership ("Highland Capital VII-C"). The general partner of Highland Capital VII-C is HMP VII LP. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. The shares are held directly by Highland Entrepreneurs' Fund VII Limited Partnership ("Highland VII Entrepreneurs' Fund"). The general partner of Highland VII Entrepreneurs' Fund is HMP VII LP. Mr. Maeder disclaims Section 16 beneficial ownership of such securities, except to the extent, if any, of his pecuniary interest therein. This report shall not be deemed to be an admission that Mr. Maeder is the beneficial owner of such securities for purposes of Section 16 or for any other purpose. /s/ Eric Pyenson, as attorney-in-fact 2018-08-06