Cabot Corp (CBT) SVP awarded 3,486 shares and 12,767 stock options

Rhea-AI Filing Summary

Cabot Corporation reported an equity compensation grant to Senior Vice President William F. Masterson III. On December 3, 2025, he acquired 3,486 shares of Cabot common stock at a price of $0, increasing his directly held stake to 7,210 shares. This indicates a stock award rather than an open-market purchase.

On the same date, he also received an employee stock option to buy 12,767 Cabot common shares at an exercise price of $64.54 per share. The option is scheduled to vest over three years: 30% on December 3, 2026, 30% on December 3, 2027, and 40% on December 3, 2028, and will expire on December 2, 2035. These awards align his compensation more closely with Cabot’s long-term share performance.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Masterson William F III

(Last) (First) (Middle)

C/O CABOT CORPORATION

TWO SEAPORT LANE, SUITE 1400

(Street)

BOSTON MA 02210

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
CABOT CORP [ CBT ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Senior Vice President

3. Date of Earliest Transaction (Month/Day/Year)
12/03/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	12/03/2025		A		3,486	A	$0	7,210	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option (Right to Buy)	$64.54	12/03/2025(1)		A		12,767		(1)	12/02/2035	Common Stock	12,767	$0	12,767	D

Explanation of Responses:

1. The option vests over a three year period as follows: 30% on December 3, 2026, 30% on December 3, 2027 and 40% on December 3, 2028.

	By: Jennifer Lombardi, pursuant to a power of attorney from William F. Masterson, III	12/05/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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FAQ

What insider transaction did Cabot Corp (CBT) report for William F. Masterson III?

Cabot Corp reported that Senior Vice President William F. Masterson III received 3,486 shares of common stock at a price of $0 and an employee stock option for 12,767 shares on December 3, 2025.

How many Cabot Corp (CBT) shares does the executive hold after this transaction?

Following the stock award of 3,486 shares on December 3, 2025, the executive beneficially owns 7,210 Cabot common shares in direct ownership.

What are the terms of the new employee stock option reported by Cabot Corp (CBT)?

The employee stock option covers 12,767 Cabot common shares at an exercise price of $64.54 per share, is directly owned, and expires on December 2, 2035.

How does the Cabot Corp (CBT) stock option for the executive vest over time?

The option vests over three years: 30% on December 3, 2026, 30% on December 3, 2027, and 40% on December 3, 2028.

Was the Cabot Corp (CBT) insider transaction a purchase on the open market?

No. The reported 3,486 Cabot common shares were acquired at a price of $0, which indicates they were granted as part of equity compensation rather than bought on the open market.

What is the ownership form of the Cabot Corp (CBT) securities held by the executive after this filing?

Both the 7,210 shares of Cabot common stock and the 12,767 stock options are reported as held in direct ownership.