Biogen Inc. (BIIB)

NMS – Real Time Price. Currency in USD

199.36

+1.41 (0.71%)

At close: May 12, 2026, 4:00 PM EDT

199.50

+0.14 (0.07%)

After-hours: May 12, 2026, 7:18 PM EDT

Ownership

Breakdown
0.18%	% of Shares Held by All Insider
97.55%	% of Shares Held by Institutions
97.73%	% of Float Held by Institutions
1437	Number of Institutions Holding Shares

Holder	Shares	Date Reported	% Out	Value
Primecap Management Company	14.76M	2026-03-31	10.00%	$2.97B
Vanguard Capital Management LLC	9.54M	2026-03-31	6.46%	$1.92B
Vanguard Portfolio Management LLC	6.53M	2026-03-31	4.42%	$1.31B

Holder	Shares	Date Reported	% Out	Value
VANGUARD CHESTER FUNDS-Vanguard PRIMECAP Fund	8.36M	2025-12-31	5.66%	$1.68B
VANGUARD INDEX FUNDS-Vanguard Total Stock Market Index Fund	4.63M	2025-12-31	3.13%	$929.27M
VANGUARD INDEX FUNDS-Vanguard 500 Index Fund	3.70M	2025-12-31	2.51%	$743.41M
Fidelity Contrafund	3.27M	2026-03-31	2.21%	$656.91M
VANGUARD INDEX FUNDS-Vanguard Mid-Cap Index Fund	3.19M	2025-12-31	2.16%	$641.59M
VANGUARD SPECIALIZED FUNDS-Vanguard Health Care Fund	2.91M	2026-01-31	1.97%	$585.41M
VANGUARD HORIZON FUNDS-Vanguard Capital Opportunity Fund	2.33M	2025-12-31	1.58%	$468.66M
iShares Trust-iShares Core S&P 500 ETF	1.89M	2026-03-31	1.28%	$379.14M
Fidelity Concord Street Trust-Fidelity 500 Index Fund	1.87M	2026-03-31	1.27%	$376.57M
SPDR S&P 500 ETF TRUST	1.79M	2025-12-31	1.22%	$340.88M
SPDR S&P 500 ETF Trust	1.79M	2025-12-31	1.22%	$335.55M
SPDR S&P 500 ETF TRUST-State Street SPDR S&P 500 ETF Trust	1.76M	2026-04-30	1.19%	$353.68M