Cosan (NYSE: CSAN) director discloses large indirect share stakes

Rhea-AI Filing Summary

Cosan S.A. director Rubens Ometto Silveira Mello has filed an initial ownership report detailing his indirect holdings of the company’s common stock. The filing lists 712,702,674 shares held through Aguassanta Participacoes S.A., 109,532,616 shares held through Queluz Holdings Limited, and 77,640 shares held through Rio das Pedras Acoes.

These are reported as indirect positions, reflecting share ownership through affiliated entities rather than direct personal holdings, and the filing does not record any new buy or sell transactions.

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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

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1. Name and Address of Reporting Person^*

Mello Rubens Ometto Silveira

(Last) (First) (Middle)

AVENIDA BRIGADEIRO FARIA LIMA 4100

(Street)

SAO PAULO SP 04543132

(City) (State) (Zip)

BRAZIL

(Country)

2. Date of Event Requiring Statement (Month/Day/Year)
03/18/2026

3. Issuer Name and Ticker or Trading Symbol
Cosan S.A. [ CSAN ]

3a. Foreign Trading Symbol
[CSAN3]

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

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

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

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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	712,702,674	I	Aguassanta Participacoes S.A.
Common Stock1	109,532,616	I	Queluz Holdings Limited
Common Stock1	77,640	I	Rio das Pedras Acoes

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

Remarks:

1 Common stock represented by American Depositary Shares. Each American Depositary Share represents four shares of Common Stock.

	/s/ Rubens Ometto Silveira Mello	03/24/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 3: SEC 1473 (03-26)

FAQ

What does Cosan (CSAN) director Rubens Ometto report in this Form 3?

He reports indirect ownership of Cosan common stock through affiliated entities. The filing lists large positions held via Aguassanta Participacoes S.A., Queluz Holdings Limited, and Rio das Pedras Acoes, establishing his initial beneficial ownership baseline as a company insider.

How many Cosan (CSAN) shares are reported through Aguassanta Participacoes S.A.?

The filing shows 712,702,674 Cosan common shares held indirectly through Aguassanta Participacoes S.A. This stake is attributed to director Rubens Ometto Silveira Mello as an indirect holding, rather than shares registered directly in his own name.

What indirect Cosan (CSAN) holdings are reported via Queluz Holdings Limited?

The Form 3 indicates 109,532,616 Cosan common shares held indirectly through Queluz Holdings Limited. This position is part of Rubens Ometto Silveira Mello’s total reported beneficial ownership in the company as a board member.

Are there additional Cosan (CSAN) shares held through Rio das Pedras Acoes?

Yes. The filing reports 77,640 Cosan common shares held indirectly via Rio das Pedras Acoes. Together with the larger positions held through other entities, this contributes to the director’s overall reported indirect ownership in Cosan.

Does this Cosan (CSAN) Form 3 show any insider buying or selling?

No. The Form 3 records existing indirect holdings rather than new trades. All three line items are classified as holdings, and the transaction summary shows no buy, sell, exercise, gift, or tax-withholding transactions reported in this disclosure.