MAT: Stanichi Roberto Seixas discloses securities transactions

By AlphaYouPublished Oct 2, 2026Form 4

Stocks in this disclosure

Reported activity

Stanichi Roberto Seixas

Reporting filer

Stanichi Roberto Seixas reported Exercise or conversion in MATTEL INC /DE/: 1715 units of Common Stock, dated 2026-09-30. The full Form 4 contains 3 transaction entries.

Disclosed: Oct 2, 2026

Reported details

3 entries

All validated entries in this disclosure
Security	Owner	Date	Code	Action	Quantity	Price	Following holdings	Reporting delay	Filed terms and references
Common Stock	Stanichi Roberto Seixas	2026-09-30	M	Exercise or conversion	1715	Not stated (see footnotes)	47,644	2 days	Filed terms security Title: Common Stock transaction Date: 2026-09-30 transaction Form Type: 4 transaction Code: M equity Swap Involved: 0 transaction Shares: 1715 id: F1 transaction Acquired Disposed Code: A shares Owned Following Transaction: 47644 direct Or Indirect Ownership: D
Common Stock	Stanichi Roberto Seixas	2026-09-30	F	Tax/exercise withholding	873	12.66	46,771	2 days	Filed terms security Title: Common Stock transaction Date: 2026-09-30 transaction Form Type: 4 transaction Code: F equity Swap Involved: 0 transaction Shares: 873 id: F2 transaction Price Per Share: 12.66 transaction Acquired Disposed Code: D shares Owned Following Transaction: 46771 direct Or Indirect Ownership: D
Restricted Stock Units (derivative)	Stanichi Roberto Seixas	2026-09-30	M	Exercise or conversion	1715	0	3,484	2 days	Filed terms security Title: Restricted Stock Units id: F1 transaction Date: 2026-09-30 transaction Form Type: 4 transaction Code: M equity Swap Involved: 0 transaction Shares: 1715 transaction Price Per Share: 0 transaction Acquired Disposed Code: D id: F1 id: F1 underlying Security Title: Common Stock underlying Security Shares: 1715 shares Owned Following Transaction: 3484 direct Or Indirect Ownership: D

Common Stock

Owner: Stanichi Roberto Seixas
Date: 2026-09-30
Code: M
Action: Exercise or conversion
Quantity: 1715
Price: Not stated (see footnotes)
Following holdings: 47,644
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-09-30
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
transaction Shares: 1715
id: F1
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 47644
direct Or Indirect Ownership: D

Common Stock

Owner: Stanichi Roberto Seixas
Date: 2026-09-30
Code: F
Action: Tax/exercise withholding
Quantity: 873
Price: 12.66
Following holdings: 46,771
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Common Stock
transaction Date: 2026-09-30
transaction Form Type: 4
transaction Code: F
equity Swap Involved: 0
transaction Shares: 873
id: F2
transaction Price Per Share: 12.66
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 46771
direct Or Indirect Ownership: D

Restricted Stock Units (derivative)

Owner: Stanichi Roberto Seixas
Date: 2026-09-30
Code: M
Action: Exercise or conversion
Quantity: 1715
Price: 0
Following holdings: 3,484
Reporting delay: 2 days
Filed terms and references: Filed terms
security Title: Restricted Stock Units
id: F1
transaction Date: 2026-09-30
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
transaction Shares: 1715
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F1
id: F1
underlying Security Title: Common Stock
underlying Security Shares: 1715
shares Owned Following Transaction: 3484
direct Or Indirect Ownership: D

Purchases, sales, grants and option exercises are different transactions. The reported code identifies the action; it does not establish a motive.

Filing context

Quantities and prices are shown in the units filed. No trade value is inferred from their product.
Stanichi Roberto Seixas: Pres., Chief Mktg & Brand Ofc.
F1: As reported on a Form 3 dated July 29, 2026 and filed on August 4, 2026, the Reporting Person received a grant of 5,199 Restricted Stock Units ("RSUs" or "Units") on September 30, 2025. The RSUs vest as to (a) 33% of the Units granted on the first anniversary of the date of grant, (b) an additional 33% of the Units granted on the second anniversary of the date of grant, and (c) the remaining 34% of the Units granted on the third anniversary of the date of grant. On each vesting date, for each Unit vesting on such date, the Reporting Person will receive one share of Mattel, Inc. Common Stock, subject to tax withholding. On September 30, 2026, the first 33% of these RSUs vested, resulting in the issuance of 1,715 shares of Mattel, Inc. Common Stock.
F2: Pursuant to the terms of the September 30, 2025 RSU grant, 873 shares of Mattel, Inc. Common Stock were automatically withheld at vesting to cover required tax withholding.

Original sources

SEC ownership filing

Prepared automatically from public filing data. Report a correction.

Security

Owner

Date

Code

Action

Quantity

Price

Following holdings

Reporting delay

Filed terms and references

Common Stock

Stanichi Roberto Seixas

2026-09-30

Exercise or conversion

1715

Not stated (see footnotes)

47,644

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-09-30
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
transaction Shares: 1715
id: F1
transaction Acquired Disposed Code: A
shares Owned Following Transaction: 47644
direct Or Indirect Ownership: D

Common Stock

Stanichi Roberto Seixas

2026-09-30

Tax/exercise withholding

873

12.66

46,771

2 days

Filed terms

security Title: Common Stock
transaction Date: 2026-09-30
transaction Form Type: 4
transaction Code: F
equity Swap Involved: 0
transaction Shares: 873
id: F2
transaction Price Per Share: 12.66
transaction Acquired Disposed Code: D
shares Owned Following Transaction: 46771
direct Or Indirect Ownership: D

Restricted Stock Units (derivative)

Stanichi Roberto Seixas

2026-09-30

Exercise or conversion

1715

3,484

2 days

Filed terms

security Title: Restricted Stock Units
id: F1
transaction Date: 2026-09-30
transaction Form Type: 4
transaction Code: M
equity Swap Involved: 0
transaction Shares: 1715
transaction Price Per Share: 0
transaction Acquired Disposed Code: D
id: F1
id: F1
underlying Security Title: Common Stock
underlying Security Shares: 1715
shares Owned Following Transaction: 3484
direct Or Indirect Ownership: D

Filing context

Quantities and prices are shown in the units filed. No trade value is inferred from their product.

Stanichi Roberto Seixas: Pres., Chief Mktg & Brand Ofc.

F1: As reported on a Form 3 dated July 29, 2026 and filed on August 4, 2026, the Reporting Person received a grant of 5,199 Restricted Stock Units ("RSUs" or "Units") on September 30, 2025. The RSUs vest as to (a) 33% of the Units granted on the first anniversary of the date of grant, (b) an additional 33% of the Units granted on the second anniversary of the date of grant, and (c) the remaining 34% of the Units granted on the third anniversary of the date of grant. On each vesting date, for each Unit vesting on such date, the Reporting Person will receive one share of Mattel, Inc. Common Stock, subject to tax withholding. On September 30, 2026, the first 33% of these RSUs vested, resulting in the issuance of 1,715 shares of Mattel, Inc. Common Stock.

F2: Pursuant to the terms of the September 30, 2025 RSU grant, 873 shares of Mattel, Inc. Common Stock were automatically withheld at vesting to cover required tax withholding.