Holocene Advisors’s Biogen BIIB Stock Holding History

Holocene Advisors’s Portfolio BIIB Stock Details BIIB Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$879K	Buy	+4,793	New	+$883K	﹤0.01%	690
2025 Q4	–	Sell	-5,979	Closed	-$838K	–	753
2025 Q3	$838K	Buy	+5,979	New	+$808K	﹤0.01%	639
2023 Q3	–	Sell	-3,791	Closed	-$1.08M	–	722
2023 Q2	$1.08M	Sell	3,791 -190,314	-98%	-$56.7M	﹤0.01%	627
2023 Q1	$54M	Buy	+194,105	New	+$53.7M	0.27%	125
2021 Q3	–	Sell	-1,370	Closed	-$474K	–	812
2021 Q2	$474K	Buy	+1,370	New	+$415K	﹤0.01%	750
2020 Q2	–	Sell	-227,469	Closed	-$68.4M	–	618
2020 Q1	$72M	Sell	227,469 -22,473	-9%	-$6.82M	0.77%	33
2019 Q4	$74.2M	Buy	+249,942	New	+$69.3M	0.66%	50
2018 Q2	–	Sell	-926	Closed	-$254K	–	578
2018 Q1	$254K	Buy	+926	New	+$287K	0.01%	432

Other funds holding BIIB

BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return

Primecap Management Pasadena, California $127B AUM 44.11% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

VPM

Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM

Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

Wellington Management Group Boston, Massachusetts $535B AUM 26.23% 1-Year Est. Return

Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return

JP Morgan Chase New York $1.56T AUM 27.86% 1-Year Est. Return

Holocene Advisors's BIIB Position: Q1 2026 in Review

Holocene Advisors opened a new position in Biogen (BIIB) in Q1 2026: 4,793 shares worth $879K. The stake represents ﹤0.01% of the portfolio and ranks #690 among its holdings. This is a return to the name: Holocene Advisors previously reported a position in BIIB as recently as Q3 2025.

Holocene Advisors first reported a position in BIIB in Q1 2018 and has held it in 8 quarters since. The position peaked at $74.2M in Q4 2019. 1,002 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.

Holocene Advisors held 4,793 shares of Biogen worth $879K as of Q1 2026.
Biogen was a new Holocene Advisors position in Q1 2026.
Biogen made up ﹤0.01% of Holocene Advisors's portfolio in Q1 2026, its #690 holding.
Holocene Advisors first reported a position in Biogen in Q1 2018 and has held it in 8 quarters since.
Holocene Advisors's Biogen position peaked at $74.2M in Q4 2019.
1,002 funds tracked by Wall St. Rank held Biogen as of Q1 2026.

Based on Holocene Advisors's 13F filing for Q1 2026, filed 15 May 2026.