BIIB Insider Activity: Rowinsky Boosts Stake by 2,370 Shares at $0 Cost

Rhea-AI Filing Summary

Biogen Inc. (BIIB) – Form 4 insider transaction

Director Eric K. Rowinsky reported the acquisition of 2,370 shares of Biogen common stock on 06/17/2025. The filing lists the transaction code “A,” indicating the shares were acquired rather than sold; the stated price is $0.00, suggesting a board-related equity grant or similar stock-based award. Following the transaction, Rowinsky’s direct beneficial ownership increased to 24,339 shares, up from 21,969 shares—an increase of roughly 11%.

No derivative securities were reported, and there were no dispositions. The filing was signed on 06/18/2025 by an attorney-in-fact.

From an investment perspective, the event is routine and low-impact: it reflects standard director compensation and modestly tightens alignment between the board member and shareholders without affecting Biogen’s capital structure or cash flows.

Positive

• Increased insider ownership: Director’s stake rose by 2,370 shares, aligning governance interests with shareholders.

Negative

• None.

Insights

Securities Analyst

TL;DR: Director granted 2,370 free shares; no sales, minimal market impact.

The Form 4 shows Eric K. Rowinsky, a director, received 2,370 Biogen shares at a zero stated cost on 06/17/2025, raising his direct stake to 24,339 shares. The “A” code and $0 price point to a routine equity award, not an open-market purchase. There were no derivative positions reported. Such grants marginally improve insider alignment but do not signal a trading view or alter share count materially. For investors, the disclosure is informational rather than catalytic.

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
Estimated average burden
hours per response:			0.5

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^*

Rowinsky Eric K

(Last) (First) (Middle)

BIOGEN INC.

225 BINNEY STREET

(Street)

CAMBRIDGE MA 02142

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
BIOGEN INC. [ BIIB ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
06/17/2025

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	06/17/2025		A		2,370	A	$0	24,339	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

Explanation of Responses:

	/s/ Wendell Taylor, Attorney in Fact for Eric K. Rowinsky	06/18/2025
	** 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 4 (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.

FAQ

How many Biogen (BIIB) shares did Director Eric K. Rowinsky acquire?

The Form 4 reports an acquisition of 2,370 common shares.

Was the transaction a purchase or an award?

The filing lists transaction code "A" and a $0.00 price, indicating an equity award rather than a market purchase.

What is Rowinsky’s total direct ownership after the transaction?

Following the award, he directly beneficially owns 24,339 Biogen shares.

Did the Form 4 include any sales or derivative security activity?

No. The filing shows no dispositions and no derivative securities were reported.

Does this insider transaction materially impact Biogen’s share count or earnings?

No. The award is immaterial relative to Biogen’s outstanding shares and has no effect on earnings or cash flow.