BIOGEN INC.

BIIBNASDAQ

$222.89-0.70 (-0.31% today)

Legend

Insider buy

Insider sell

Congress buy

Congress sell

Hedge Funds
bought vs soldGreener markers show more buyers; redder markers show more sellers.

Company share activityNet buybacksNo changeNet dilution

Marker size reflects transaction size.

Insider buy
Insider sell
Congress buy
Congress sell
Hedge Funds bought vs sold

Share activityNet buybacksNo changeNet dilution

Marker size reflects transaction size. Greener fund markers mean more buyers.

Insider Buy
Insider Sell
Congress Buy
Congress Sell
Hedge funds bought vs sold
BuybackNo changeNet dilution

BIOGEN INC. price and activity chart data

Showing the 1Y range: Oct 6, 2025 to Oct 6, 2026. Price (+44.7%). 0 insider or congressional trades plotted in this window as 0 markers; nearby trades of the same kind are grouped.

Transactions plotted on the price chart
Date	Category	Person	Role	Action	Amount	Change in holding

Largest institutional holders

13F · Q2 2026

Fund	% of company held	Value	% of portfolio	Quarterly activity
FMR LLC	12.34%	$3.94B	0.17%	Not reported
BlackRock, Inc.	10.83%	$3.45B	0.05%	Not reported
Primecap Management Co	10.26%	$3.27B	1.94%	Add 2.69%
Vanguard Capital Management LLC	6.54%	$2.09B	0.04%	Not reported
State Street Corp	4.97%	$1.59B	0.05%	Not reported
Vanguard Portfolio Management LLC	4.47%	$1.43B	0.06%	Not reported
Geode Capital Management, LLC	3.01%	$958M	0.05%	Not reported
Wellington Management Group LLP	2.11%	$674M	0.12%	Add 5.26%
Norges Bank	1.75%	$557M	0.06%	Not reported
Morgan Stanley	1.63%	$521M	0.03%	Not reported
AQR Capital Management LLC	1.31%	$417M	0.15%	Not reported
JPMorgan Chase & Co	1.23%	$395M	0.02%	Not reported
Invesco Ltd.	1.22%	$390M	0.03%	Not reported
Amundi	1.03%	$328M	0.08%	Not reported
Legal & General Group Plc	1.01%	$323M	0.07%	Not reported
Northern Trust Corp	0.97%	$309M	0.04%	Not reported
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC	0.85%	$271M	0.05%	Not reported
Goldman Sachs Group Inc	0.83%	$266M	0.02%	Not reported
Dimensional Fund Advisors LP	0.78%	$248M	0.05%	Not reported
Pacer Advisors, Inc.	0.76%	$243M	0.62%	Add 70.04%
Charles Schwab Investment Management Inc	0.76%	$241M	0.03%	Not reported
Bank of America Corp	0.76%	$241M	0.02%	Not reported
UBS Group AG	0.70%	$223M	0.03%	Not reported
Alyeska Investment Group, L.P.	0.63%	$201M	0.52%	Not reported
Deutsche Bank Ag\	0.61%	$193M	0.06%	Not reported
Pictet Asset Management Holding SA	0.58%	$184M	0.18%	Reduce 6.73%
Vanguard Fiduciary Trust Co	0.56%	$179M	0.04%	Not reported
Robeco Institutional Asset Management B.V.	0.54%	$171M	0.21%	Add 3.66%
Fred Alger Management, LLC	0.53%	$170M	0.57%	Add 7.52%
Bank of New York Mellon Corp	0.52%	$167M	0.03%	Not reported
Massachusetts Financial Services Co	0.50%	$163M	0.05%	Add 3.37%
Citigroup Inc	0.50%	$159M	0.05%	Not reported
Royal Bank of Canada	0.48%	$153M	0.02%	Not reported
Employees Provident Fund Board	0.48%	$152M	0.87%	Not reported
First Trust Advisors LP	0.46%	$147M	0.09%	Add 1.20%
AustralianSuper Pty Ltd	0.46%	$145M	0.63%	Add 9.17%
Artemis Investment Management LLP	0.39%	$123M	1.10%	Reduce 0.10%
Zurcher Kantonalbank (Zurich Cantonalbank)	0.37%	$117M	0.22%	Not reported
Caisse de depot et placement du Quebec	0.35%	$110M	0.16%	Reduce 1.64%
LSV Asset Management	0.30%	$95.9M	0.17%	Add 33.05%
Citadel Advisors LLC	0.28%	$90.4M	0.01%	Not reported
Swiss National Bank	0.28%	$89.4M	0.05%	Not reported
National Pension Service	0.28%	$87.7M	0.06%	Add 1.09%
BNP Paribas Financial Markets	0.26%	$83.7M	0.03%	Not reported
Mitsubishi UFJ Asset Management Co., Ltd.	0.24%	$77.5M	0.04%	Add 7.30%
Sumitomo Mitsui Trust Group, Inc.	0.23%	$74.9M	0.04%	Reduce 2.72%
Victory Capital Management Inc	0.23%	$74.2M	0.04%	Not reported
FIL Ltd	0.23%	$74M	0.05%	Add 7.72%
Fisher Asset Management, LLC	0.23%	$73M	0.02%	Add 8.12%
Vanguard Global Advisers, LLC	0.23%	$72.6M	0.03%	Not reported

50 of 975 holders

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