X0306 5 2017-12-31 0 0 0 0001610532 Hortonworks, Inc. HDP 0001626464 Volpi Michelangelo C/O HORTONWORKS, INC. 5470 GREAT AMERICA PARKWAY SANTA CLARA CA 95054 1 0 0 0 Common Stock 2017-06-26 5 G 0 12998 0.00 D 10838 D Common Stock 1552425 I By Index Ventures IV (Jersey), L.P. Common Stock 147355 I By Index Ventures IV Parallel Entrepreneur Fund (Jersey), L.P. Common Stock 1678475 I By Index Ventures V (Jersey), L.P. Common Stock 13596 I By Index Ventures V Parallel Entrepreneur Fund (Jersey), L.P. Common Stock 35124 I By Yucca (Jersey) SLP The Reporting Person is a partner within the Index Ventures group. Advisors within the Index Ventures group provide advice to Index Ventures IV (Jersey), L.P., Index Ventures IV Parallel Entrepreneur Fund (Jersey), L.P., Index Ventures V (Jersey), L.P., Index Ventures V Parallel Entrepreneur Fund (Jersey), L.P. and Yucca (Jersey) SLP (the "Index Funds"). The Reporting Person is involved in making recommendations to the Index funds, but does not hold voting or dispositive power over the shares held by the Index Funds. The Reporting Person disclaims beneficial ownership of these securities, except to the extent of his pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of such securities for Section 16 or any other purpose. /s/ David Howard as Attorney-in-Fact for Michelangelo Volpi 2018-02-15