Arm Holdings (ARM) director Jeffrey Sine files initial ownership report

Rhea-AI Filing Summary

ARM Holdings plc director Jeffrey Sine filed an initial statement of beneficial ownership. He directly holds 7,431 Ordinary Shares, represented by American Depositary Shares. He also holds restricted stock units covering 2,141 underlying Ordinary Shares that are scheduled to vest in full on May 15, 2026, subject to continued service. Each RSU will deliver one Ordinary Share in ADS form after vesting.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Sine Jeffrey

Role Director

Type	Security	Shares	Price	Value
holding	Restricted Stock Units	--	--	--
holding	Ordinary Shares	--	--	--

Holdings After Transaction: Restricted Stock Units — 2,141 shares (Direct); Ordinary Shares — 7,431 shares (Direct)

Footnotes (1)

1. Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share. The restricted stock units ("RSUs") will vest in full on May 15, 2026, subject to continued service to Arm Holdings plc. Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS.

Understanding Insider Trading Forms →

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

OMB APPROVAL

OMB Number:			3235-0104
Estimated average burden
hours per response:			0.5

1. Name and Address of Reporting Person^*

Sine Jeffrey

(Last) (First) (Middle)

C/O ARM HOLDINGS PLC

110 FULBOURN ROAD

(Street)

CAMBRIDGE CB1 9NJ

(City) (State) (Zip)

UNITED STATES

(Country)

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

3. Issuer Name and Ticker or Trading Symbol
ARM HOLDINGS PLC /UK [ ARM ]

3a. Foreign Trading Symbol

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)
Ordinary Shares(1)	7,431	D

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
Restricted Stock Units	(2)	(2)	Ordinary Shares(1)	2,141	(3)	D

Explanation of Responses:

1. Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share.

2. The restricted stock units ("RSUs") will vest in full on May 15, 2026, subject to continued service to Arm Holdings plc.

3. Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS.

Remarks:

Exhibit 24 - Power of Attorney

	/s/ George Kanelos, as Attorney-in-Fact for Jeffrey Sine	03/18/2026
	** 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 Jeffrey Sine report owning in this Form 3 for ARM?

Jeffrey Sine reports direct ownership of 7,431 Ordinary Shares of ARM, held in the form of American Depositary Shares. He also reports restricted stock units over 2,141 underlying Ordinary Shares, which can convert into shares once they vest according to the award terms.

How are ARM (ARM) Ordinary Shares held according to this filing?

The filing states that ARM Ordinary Shares, nominal value 0.001 GBP, are held in the form of American Depositary Shares (ADSs). Each ADS represents one Ordinary Share, giving U.S. investors an easier way to hold and trade the company’s equity.

When do Jeffrey Sine’s ARM restricted stock units vest?

The restricted stock units reported by Jeffrey Sine will vest in full on May 15, 2026, subject to his continued service to Arm Holdings plc. Once vested, each RSU entitles him to receive one Ordinary Share delivered in ADS form.

How many ARM shares underlie Jeffrey Sine’s restricted stock units?

Jeffrey Sine’s restricted stock units cover 2,141 underlying Ordinary Shares of ARM. After vesting on May 15, 2026, each RSU will convert into one Ordinary Share, also held as an American Depositary Share according to the filing footnotes.

Does this ARM Form 3 show any insider buying or selling activity?

This Form 3 reports holdings rather than trades, with transaction codes marked as unknown and no share amounts listed as bought or sold. It establishes Jeffrey Sine’s initial ownership in Ordinary Shares and restricted stock units as a director of Arm Holdings plc.