Biogen Ownership & Insider Activity

Biogen (BIIB) institutional and insider ownership, recent insider transactions and ownership breakdown.

Insiders own 1.5% of shares outstanding. Institutional investors hold 76.4%. Over the past 90 days, insiders made 1 sale worth $240K.

Shares Outstanding

147.754M

Shares Float

132.539M

Insider Shares Owned

2.250M

Insider % Owned

1.5%

Institutional Shares Held

112.922M

Institutional % Held

76.4%

Ownership Breakdown

Net Insider Activity by Month

Purchases (90d)

Sales (90d)

$240K total

Net Activity

Net Selling

Net Value (90d)

-$240K

Biogen Insider Transactions (Last 6 Months)

Date	Insider	Title	Type	Shares	Price	Value
Aug 3, 2026	Dr. Minor	DIRECTOR	SELL	1.186K	$202.15	$240K

Date	Member	Party	Chamber	Action	Amount
Aug 18, 2026	Kevin Hern	R	House	Sale	$1,001 - $15,000
Jun 5, 2026	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
Jun 2, 2026	Maria Elvira Salazar	R	House	Sale	$15,001 - $50,000
May 12, 2026	Maria Elvira Salazar	R	House	Purchase	$1,001 - $15,000
May 11, 2026	Maria Elvira Salazar	R	House	Purchase	$1,001 - $15,000
May 11, 2026	Maria Elvira Salazar	R	House	Purchase	$50,001 - $100,000
Mar 27, 2026	Alan Armstrong	R	Senate	Purchase	$1,001 - $15,000
Jan 30, 2026	Gilbert Ray Cisneros	D	House	Purchase	$1,001 - $15,000
May 15, 2025	Robert Bresnahan	R	House	Purchase	$1,001 - $15,000
Apr 8, 2025	Robert Bresnahan	R	House	Sale	$1,001 - $15,000
Feb 25, 2025	Robert Bresnahan	R	House	Purchase	$1,001 - $15,000