CABOT CORP — Director's Dealing 2018

May 18, 2018

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2018-05-16

Reporting Person: Prevost Patrick M. (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2018-05-16	Common Stock	M	70240	$47.62	Acquired	353285	Direct
2018-05-16	Common Stock	S	70240	$61.34	Disposed	283045	Direct
2018-05-16	Common Stock	M	84821	$46.03	Acquired	367866	Direct
2018-05-16	Common Stock	S	84821	$61.56	Disposed	283045	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2018-05-16	Employee Stock Option (Right to Buy)	$47.62	M	70240	Disposed	2019-10-15	Common Stock (70240)	Direct
2018-05-16	Employee Stock Option (Right to Buy)	$46.03	M	84821	Disposed	2019-10-15	Common Stock (84821)	Direct

Footnotes

F1: The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $61.10 to $61.56, 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.

F2: The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $61.27 to $61.95, 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.

F3: 72,440 shares were subject to the option. The option vested over a three year period as follows: 30% on November 8, 2014, 30% on November 8, 2015 and 40% on July 23, 2016.

F4: 84,821 shares were subject to the option. The option vested as follows: 30% on November 14, 2015 and 70% on July 23, 2016.