X0306 4 2019-12-12 0 0000016040 CABOT CORP CBT 0001671755 Kalkstein Hobart C/O CABOT CORPORATION TWO SEAPORT LANE, SUITE 1300 BOSTON MA 02210 0 1 0 0 Senior Vice President Common Stock 2019-12-12 4 S 0 2833 48.34 D 40954 D Common Stock 2019-12-13 4 S 0 1167 48.75 D 39787 D Common Stock 6342.87 I Through the Trustee for the Corporation's 401(k) Plan The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $48.33 to $48.38, 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. By: Kristine L. Ouimet, pursuant to a power of attorney from Hobart C. Kalkstein 2019-12-16