X0306 4 2016-04-20 0 0001610532 Hortonworks, Inc. HDP 0001626708 Cunitz Herbert C/O HORTONWORKS, INC. 5470 GREAT AMERICA PARKWAY SANTA CLARA CA 95054 0 1 0 0 President Common Stock 2016-04-20 4 S 0 7000 11.91 D 109830 D Common Stock 2016-04-21 4 S 0 6972 12.34 D 102858 D Common Stock 230900 I See Footnote Common Stock 230900 I See Footnote Common Stock 858593 I See Footnote This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 14, 2015. Represents the weighted average sale price for the entire number of shares sold. The sale prices range from $11.76 to $12.10 per share. The Reporting Person undertakes to provide to the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares sold by the Reporting Person at each separate price within the range. Represents the weighted average sale price for the entire number of shares sold. The sale prices range from $12.04 to $12.50 per share. The Reporting Person undertakes to provide to the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares sold by the Reporting Person at each separate price within the range. Herbert D. Cunitz and Laura J. Cunitz, Trustees of the Cunitz 2014 Irrevocable Trust fbo Jaclyn L. Cunitz. Herbert D. Cunitz and Laura J. Cunitz, Trustees of the Cunitz 2014 Irrevocable Trust fbo Graham M. Cunitz. Herbert D. Cunitz and Laura J. Cunitz, Trustees of the Herbert D. Cunitz Trust dated March 17, 2000. /s/ David Howard as Attorney-in-fact for Herbert Cunitz 2016-04-22