Biogen BIIB Institutional Ownership

NASDAQ BIIB

$222.82 -3.06 (-1.35%)

At close: Oct 1, 2026 · 4:00 PM EDT

Institutions by Trading Activity

1,037 Institutions

Increased 550 53.0%

Unchanged 193 18.6%

Reduced 294 28.4%

Ownership Statistics

13F · as of 30 Jun, 2026

Institutional Ownership

97.18%

▲+5.95 pp QoQ

Shares Held by Institutions

143.53Mn

of 147.70Mn outstanding

▲+8.02% QoQ

Shares Outstanding

147.70Mn

4.17Mn held outside 13F filers

Institutional Investors

1,037

filed 13F for Jun 2026

▲+33 vs prior quarter

Net Shares Added (QoQ)

+10.66Mn

accumulated since last quarter

Value of Holdings

$32.42Bn

reported market value

Shares Owned by Institutions

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Institutions

Accumulated Distributed

Latest quarter —

Net over range —

Accumulating quarters —

Ownership Summary

Quarter ending 30 Jun, 2026

Biogen Inc. (NASDAQ:BIIB) showed up in the 13F filings of 1,036 institutional investors as of June 2026.

Their combined ownership stood at 97.2% of outstanding shares in June 2026, up from 91.2% in March 2026.
Their total shares held in BIIB increased 8.02% quarter over quarter, and separately, investors owning Biogen increased 20.33% from a year ago.
Among the 1,036 funds, 550 bought more Biogen shares, 293 sold down, and 193 held their ground.
Institutional investors collectively held 143.53Mn shares in Biogen as of June 2026, up by 10.66Mn shares quarter on quarter, and up 16.05Mn shares year over year.
FMR LLC holds the largest position in BIIB at 18.22Mn shares as of June 30, 2026, or 12.33% of shares outstanding.
The most significant purchases of BIIB for the quarter ending June 2026 came from FMR LLC (5.41Mn), NORGES BANK (2.58Mn), Pacer Advisors, Inc. (1.12Mn), Sixth Street Partners Management Company, L.P. (1.12Mn), Amundi (726.0K).
The largest sellers of Biogen for the quarter ending June 2026 were T. Rowe Price Investment Management, Inc. (1.05Mn), VAN ECK ASSOCIATES CORP (981.75K), Point72 Asset Management, L.P. (721.47K), Boston Partners (436.65K), BALYASNY ASSET MANAGEMENT L.P. (384.96K).
Per Business Quant data, the top 10 holders of Biogen for the quarter ending June 2026 are FMR LLC (18.22Mn), BlackRock, Inc. (15.99Mn), PRIMECAP MANAGEMENT CO/CA/ (15.15Mn), VANGUARD CAPITAL MANAGEMENT LLC (9.65Mn), State Street Corp (7.34Mn), VANGUARD PORTFOLIO MANAGEMENT LLC (6.6Mn), GEODE CAPITAL MANAGEMENT, LLC (4.45Mn), WELLINGTON MANAGEMENT GROUP LLP (3.12Mn), NORGES BANK (2.58Mn), Morgan Stanley (2.41Mn).

Form 13F Holdings

1,035 Institutional Holders

Report period 30 Jun, 2026

Total shares held 143.53Mn

Of outstanding 97.18%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	FMR LLC	0000315066	18,217,239	12.33%	▲5,409,698	+42.24%	$3.94Bn
2	BlackRock, Inc.	0002012383	15,985,736	10.82%	▲11,135	+0.07%	$3.45Bn
3	PRIMECAP MANAGEMENT CO/CA/	0000763212	15,154,606	10.26%	▲396,999	+2.69%	$3.27Bn
4	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	9,651,117	6.53%	▲113,700	+1.19%	$2.09Bn
5	State Street Corp	0000093751	7,344,327	4.97%	▲176,405	+2.46%	$1.59Bn
6	VANGUARD PORTFOLIO MANAGEMENT LLC	0002100121	6,604,936	4.47%	▲73,209	+1.12%	$1.43Bn
7	GEODE CAPITAL MANAGEMENT, LLC	0001214717	4,449,295	3.01%	▲106,693	+2.46%	$957.94Mn
8	WELLINGTON MANAGEMENT GROUP LLP	0000902219	3,117,469	2.11%	▲155,828	+5.26%	$673.56Mn
9	NORGES BANK	0001374170	2,580,033	1.75%	▲2,580,033	0.00%	$557.44Mn
10	Morgan Stanley	0000895421	2,411,271	1.63%	▲240,331	+11.07%	$520.98Mn
11	AQR CAPITAL MANAGEMENT LLC	0001167557	1,936,859	1.31%	▲13,302	+0.69%	$416.93Mn
12	Jpmorgan Chase & Co	0000019617	1,823,140	1.23%	▼192,869	-9.57%	$394.95Mn
13	Invesco Ltd.	0000914208	1,803,944	1.22%	▲58,689	+3.36%	$389.76Mn
14	Amundi	0001330387	1,516,831	1.03%	▲726,004	+91.80%	$327.73Mn
15	Legal & General Group Plc	0000764068	1,493,289	1.01%	▲143,457	+10.63%	$322.64Mn
16	Northern Trust Corp	0000073124	1,429,490	0.97%	▼17,089	-1.18%	$308.86Mn
17	Boston Partners	0001386060	1,263,429	0.86%	▼436,649	-25.68%	$272.85Mn
18	UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC	0000861177	1,255,168	0.85%	▼122,400	-8.89%	$271.19Mn
19	Goldman Sachs Group Inc	0000886982	1,230,390	0.83%	▲179,296	+17.06%	$265.84Mn
20	DIMENSIONAL FUND ADVISORS LP	0000354204	1,148,568	0.78%	▲69,449	+6.44%	$248.17Mn

Showing 1 to 20 of 1,035 holders