X0306 4 2016-08-23 0 0000016040 CABOT CORP CBT 0001243739 BERUBE BRIAN A C/O CABOT CORPORATION TWO SEAPORT LANE, SUITE 1300 BOSTON MA 02210 0 1 0 0 SVP, General Counsel Common Stock 2016-08-23 4 S 0 8000 49.9125 D 42622 D Common Stock 2016-08-23 4 M 0 8489 34.64 A 51111 D Common Stock 2016-08-23 4 S 0 8489 49.884 D 42622 D Common Stock 8286 I Through the Trustee for the Corporation's 401(k) plan Employee Stock Option (Right to Buy) 34.64 2016-08-23 4 M 0 8489 0.00 D 2020-11-11 Common Stock 8489 0 D The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $49.835 to $49.930, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, the Corporation or any security holder of the Corporation, upon request, full information regarding the number of shares sold at each separate price. The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $49.711 to $50.25, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, the Corporation or any security holder of the Corporation, upon request, full information regarding the number of shares sold at each separate price. Reflects retirement plan contributions by the Corporation, including contributions that have occurred since the date of the reporting person's last ownership report. 8,489 shares were subject to the option. The option vested over a three year period as follows: 30% on November 12, 2011, 30% on November 12, 2012 and 40% on November 12, 2013. By: Kristine L. Ouimet, pursuant to a power of attorney from Brian A. Berube 2016-08-24