Balyasny Asset Management’s Biogen BIIB Stock Holding History

Balyasny Asset Management’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	–	Sell	-39,900	Closed	-$7.02M	–	2911
2025 Q4	$7.02M	Buy	39,900 +38,300	+2,394%	+$6.26M	0.01%	1212
2025 Q3	$224K	Buy	+1,600	New	+$216K	﹤0.01%	2692
2024 Q4	–	Sell	-6,400	Closed	-$1.24M	–	2746
2024 Q3	$1.24M	Buy	+6,400	New	+$1.34M	﹤0.01%	1875
2020 Q2	–	Sell	-90,000	Closed	-$28.5M	–	1135
2020 Q1	$28.5M	Buy	+90,000	New	+$27.3M	0.34%	69
2018 Q4	–	Sell	-57,000	Closed	-$19.3M	–	1409
2018 Q3	$19.3M	Buy	+57,000	New	+$19.6M	0.09%	309
2017 Q1	–	Sell	-90,000	Closed	-$23.5M	–	1589
2016 Q4	$23.5M	Buy	+90,000	New	+$26.7M	0.13%	227
2016 Q1	–	Sell	-25,000	Closed	-$7.66M	–	1276
2015 Q4	$7.66M	Buy	+25,000	New	+$7.18M	0.05%	417
2015 Q1	–	Sell	-29,600	Closed	-$10M	–	944
2014 Q4	$10M	Buy	+29,600	New	+$9.58M	0.09%	297

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

Balyasny Asset Management's BIIB Position: Q1 2026 in Review

Balyasny Asset Management increased its Biogen (BIIB) stake by 6.9% in Q1 2026, buying an estimated $7.76M and bringing the position to 650,046 shares worth $119M. The position accounts for 0.15% of the portfolio, ranked #140.

Balyasny Asset Management first reported a position in BIIB in Q4 2014 and has held it in 42 quarters since. The position peaked at $174M in Q4 2017. 1,002 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.

Balyasny Asset Management held 650,046 shares of Biogen worth $119M as of Q1 2026.
Balyasny Asset Management bought 42,093 Biogen shares in Q1 2026, an estimated $7.76M.
Biogen made up 0.15% of Balyasny Asset Management's portfolio in Q1 2026, its #140 holding.
Balyasny Asset Management first reported a position in Biogen in Q4 2014 and has held it in 42 quarters since.
Balyasny Asset Management's Biogen position peaked at $174M in Q4 2017.
1,002 funds tracked by Wall St. Rank held Biogen as of Q1 2026.

Based on Balyasny Asset Management's 13F filing for Q1 2026, filed 15 May 2026.