BIOGEN INC. - COM (BIIB) Institutional Ownership

13F Institutional Holders and Ownership History from Q1 2014 to Q4 2025

Type / Class: Equity / COM
Symbol: BIIB on Nasdaq
Shares outstanding: 146,614,676
Price per share: $175.99
All holders as of 30 Sep 2025: Q3 2025
Total 13F shares: 130,372,684
Total reported value: $18,265,685,564
% of total 13F portfolios: 0.01%
Share change: +954,004
Value change: +$176,296,843
Number of holders: 886
Price from insider filings: $175.99

Reported Shares, Excluding Options vs Price

Reported Value, Excluding Options

Total Investors

Significant Owners of BIOGEN INC. - COM (BIIB) based on Schedule 13D/G filings

Filer	Ownership	Holdings Value	Nb Shares	Reporting Name	Report Period
PRIMECAP MANAGEMENT CO/CA/	10%	$2,094,853,956	14,954,697	PRIMECAP MANAGEMENT CO/CA/	30 Sep 2025
BlackRock, Inc.	8.5%	$1,502,927,856	12,506,681	BlackRock, Inc.	31 Mar 2025
STATE STREET CORP	5%	$1,025,549,213	7,321,168	STATE STREET CORPORATION	30 Sep 2025

As of 30 Sep 2025, 886 institutional investors reported holding 130,372,684 shares of BIOGEN INC. - COM (BIIB). This represents 89% of the company’s total 146,614,676 outstanding shares.

Top 25 Institutional Shareholders

The largest institutional shareholders of BIOGEN INC. - COM (BIIB) together control 63% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.

Institution	Ownership %	Shares Held	Share Change %	Portfolio %	Holdings Value
VANGUARD GROUP INC	12%	17,289,235	-0.01%	0.04%	$2,421,876,038
PRIMECAP MANAGEMENT CO/CA/	10%	14,954,697	-5.4%	1.6%	$2,094,853,953
BlackRock, Inc.	10%	14,763,952	+8.9%	0.04%	$2,068,134,447
STATE STREET CORP	5%	7,319,749	-2%	0.04%	$1,025,350,440
WELLINGTON MANAGEMENT GROUP LLP	2.9%	4,246,504	-12%	0.1%	$594,850,279
GEODE CAPITAL MANAGEMENT, LLC	2.8%	4,068,781	+3.8%	0.04%	$567,740,241
Point72 Asset Management, L.P.	2.6%	3,872,901	+1.1%	1.2%	$542,516,040
Invesco Ltd.	1.6%	2,418,127	+4.2%	0.05%	$338,731,160
MORGAN STANLEY	1.5%	2,251,535	+15%	0.02%	$315,395,300
AQR CAPITAL MANAGEMENT LLC	1.2%	1,783,581	+31%	0.16%	$248,809,475
Legal & General Group Plc	1.1%	1,593,399	+10%	0.05%	$223,203,335
NORTHERN TRUST CORP	1%	1,499,332	-2.4%	0.03%	$210,026,427
Pacer Advisors, Inc.	0.99%	1,451,249	+9.9%	0.52%	$203,290,960
UBS AM, A DISTINCT BUSINESS UNIT OF UBS ASSET MANAGEMENT AMERICAS LLC	0.98%	1,439,208	-17%	0.04%	$201,604,257
BARCLAYS PLC	0.93%	1,359,424	+70%	0.07%	$190,428,112
FMR LLC	0.88%	1,287,760	-23%	0.01%	$180,389,352
JPMORGAN CHASE & CO	0.87%	1,268,350	+27%	0.01%	$177,670,522
Balyasny Asset Management L.P.	0.84%	1,234,149	+48%	0.35%	$172,879,592
DEUTSCHE BANK AG\	0.84%	1,231,302	+9.6%	0.06%	$172,480,783
BANK OF AMERICA CORP /DE/	0.83%	1,220,018	+15%	0.01%	$170,900,120
CHARLES SCHWAB INVESTMENT MANAGEMENT INC	0.77%	1,123,349	+4.4%	0.03%	$157,358,728
MILLENNIUM MANAGEMENT LLC	0.76%	1,111,190	+64%	0.12%	$155,655,495
T. Rowe Price Investment Management, Inc.	0.73%	1,067,482	-23%	0.09%	$149,533,000
VAN ECK ASSOCIATES CORP	0.73%	1,066,931	-0.73%	0.14%	$149,456,000
GOLDMAN SACHS GROUP INC	0.73%	1,063,586	+59%	0.02%	$148,987,148

Institutional Holders of BIOGEN INC. - COM (BIIB) across Reporting Periods

Period	Reported Shares, Excl. Options	Value, Excl. Options	Value Change	Puts Notional Value	Calls Notional Value	Price (Median)	Investors
2025 Q4	1,174,944	$207,170,012	+$4,862,211		$0	$175.99	149
2025 Q3	130,372,684	$18,265,685,564	+$176,296,843	$301,495,740	$505,034,873	$140.08	886
2025 Q2	129,287,238	$16,238,624,437	+$284,309,412	$299,301,011	$330,450,300	$125.59	856
2025 Q1	127,028,107	$17,371,280,984	-$578,239,538	$558,419,553	$286,262,196	$136.84	865
2024 Q4	131,405,263	$20,085,982,511	+$272,768,825	$329,465,719	$240,163,702	$152.92	861
2024 Q3	128,615,457	$24,913,936,182	-$143,640,766	$244,164,314	$182,248,736	$193.84	903
2024 Q2	128,193,288	$29,710,612,652	-$84,741,446	$284,001,854	$239,306,530	$231.82	933
2024 Q1	128,518,741	$27,691,040,526	+$55,007,555	$254,853,889	$251,171,229	$215.63	932
2023 Q4	127,982,276	$33,111,816,739	+$901,376,761	$398,054,487	$544,645,568	$258.77	993
2023 Q3	124,470,870	$31,994,071,856	-$470,206,356	$437,522,886	$478,873,638	$257.01	954
2023 Q2	126,306,466	$35,966,219,806	+$277,366,431	$517,702,711	$474,214,258	$284.85	994
2023 Q1	125,053,711	$34,758,696,486	+$300,589,329	$556,294,999	$637,213,845	$278.03	987
2022 Q4	124,528,759	$34,492,440,417	+$242,887,240	$1,172,186,380	$979,696,444	$276.92	1,018
2022 Q3	123,323,995	$32,917,825,335	+$384,787,916	$1,335,777,500	$1,518,503,400	$267.00	966
2022 Q2	121,790,135	$24,840,540,438	-$152,960,663	$699,077,660	$618,506,066	$203.94	911
2022 Q1	122,616,063	$25,827,895,030	-$220,078,557	$705,134,820	$608,114,540	$210.60	941
2021 Q4	123,500,078	$29,628,123,955	-$101,746,917	$1,391,414,696	$880,381,592	$239.92	996
2021 Q3	123,461,166	$34,947,282,206	-$614,669,326	$1,572,313,973	$1,130,997,900	$282.99	1,026
2021 Q2	125,522,812	$43,460,004,330	-$566,581,701	$1,652,864,969	$1,584,013,592	$346.27	1,091
2021 Q1	127,388,312	$35,598,424,357	-$380,775,241	$1,252,767,350	$1,266,372,400	$279.75	1,079
2020 Q4	128,905,111	$31,559,604,046	-$521,085,738	$1,401,024,620	$1,394,898,238	$244.86	1,047
2020 Q3	130,781,613	$37,077,214,726	-$1,220,436,591	$1,311,753,000	$1,066,554,000	$283.68	1,036
2020 Q2	134,944,833	$36,078,566,447	-$2,622,299,974	$1,205,758,000	$675,767,000	$267.55	1,048
2020 Q1	144,371,093	$45,633,042,157	-$2,072,462,238	$1,296,456,000	$1,021,106,000	$316.38	1,090
2019 Q4	150,927,624	$44,753,934,396	-$2,257,146,159	$1,467,812,000	$1,078,211,000	$296.73	1,090
2019 Q3	159,069,579	$37,018,304,080	-$348,502,414	$1,121,619,000	$943,513,000	$232.82	972
2019 Q2	160,395,186	$37,502,672,698	-$2,138,732,747	$996,993,000	$758,039,000	$233.87	1,002
2019 Q1	171,326,218	$40,468,172,998	-$1,011,646,914	$1,115,727,000	$933,941,000	$236.38	1,071
2018 Q4	175,003,235	$52,619,725,529	-$839,325,018	$1,063,063,000	$874,162,000	$300.92	1,135
2018 Q3	177,270,767	$62,594,382,952	-$269,008,690	$1,545,090,000	$972,261,000	$353.31	1,140
2018 Q2	178,340,992	$51,731,992,582	-$2,444,250,744	$1,011,961,000	$672,244,000	$290.24	1,087
2018 Q1	186,913,555	$51,164,896,552	-$488,678,007	$885,829,586	$659,157,120	$273.82	1,096
2017 Q4	188,568,529	$60,044,982,772	+$9,889,834	$1,191,600,668	$915,417,374	$318.57	1,120
2017 Q3	188,385,830	$58,970,231,587	+$472,002,826	$997,221,000	$878,146,000	$313.12	1,011
2017 Q2	187,380,108	$50,837,222,531	+$288,984,209	$982,996,000	$865,149,000	$271.36	991
2017 Q1	188,211,491	$51,456,575,196	+$4,118,247,453	$892,220,000	$728,925,000	$273.42	1,016
2016 Q4	189,394,911	$53,679,916,033	-$1,015,070,941	$1,419,536,000	$1,447,412,000	$283.58	1,021
2016 Q3	191,778,014	$60,010,956,983	+$480,242,801	$1,379,768,000	$1,320,543,000	$313.03	1,007
2016 Q2	190,842,498	$46,263,524,155	-$112,555,041	$1,065,078,000	$866,729,000	$241.82	957
2016 Q1	190,858,170	$49,747,381,290	-$388,687,634	$954,351,000	$755,989,000	$260.32	938
2015 Q4	192,339,308	$59,013,396,053	-$2,589,949,247	$1,390,791,000	$952,529,000	$306.35	965
2015 Q3	200,266,975	$58,440,502,406	-$3,822,036,876	$1,509,659,000	$937,353,000	$291.81	914
2015 Q2	211,110,431	$85,274,602,341	-$1,015,846,158	$1,414,484,000	$838,627,000	$403.94	961
2015 Q1	213,693,704	$90,176,303,862	+$321,462,904	$1,349,116,000	$742,805,000	$422.24	961
2014 Q4	213,378,369	$72,452,156,965	-$502,527,627	$1,187,651,000	$838,861,000	$339.45	877
2014 Q3	214,442,358	$70,936,086,109	-$177,791,858	$1,011,924,000	$614,054,000	$330.81	811
2014 Q2	214,744,481	$67,717,564,176	+$911,109,846	$937,883,000	$613,279,000	$315.31	777
2014 Q1	212,004,121	$64,813,130,089	-$390,248,896	$1,040,252,000	$691,642,000	$305.87	767