Atika Capital Management’s Alnylam Pharmaceuticals ALNY Stock Holding History

Atika Capital Management’s Portfolio ALNY Stock Details ALNY Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	–	Sell	-10,339	Closed	-$4.11M	–	62
2025 Q4	$4.11M	Sell	10,339 -11,867	-53%	-$5.25M	0.43%	64
2025 Q3	$10.1M	Sell	22,206 -5,494	-20%	-$2.24M	0.82%	37
2025 Q2	$9.03M	Buy	+27,700	New	+$7.66M	0.9%	32
2024 Q4	–	Sell	-31,000	Closed	-$8.53M	–	86
2024 Q3	$8.53M	Buy	31,000 +6,500	+27%	+$1.69M	0.87%	41
2024 Q2	$5.95M	Buy	+24,500	New	+$3.87M	0.58%	57
2021 Q4	–	Sell	-64,000	Closed	-$12.1M	–	90
2021 Q3	$12.1M	Buy	+64,000	New	+$12M	0.72%	51
2018 Q3	–	Sell	-23,000	Closed	-$2.27M	–	87
2018 Q2	$2.27M	Sell	23,000 -18,000	-44%	-$1.79M	0.44%	73
2018 Q1	$4.88M	Buy	41,000 +16,000	+64%	+$2.06M	1.67%	26
2017 Q4	$3.18M	Hold	25,000	–	–	1.23%	38
2017 Q3	$2.94M	Buy	+25,000	New	+$2.13M	0.84%	48
2016 Q4	–	Sell	-22,000	Closed	-$1.49M	–	57
2016 Q3	$1.49M	Buy	22,000 +8,000	+57%	+$564K	0.61%	57
2016 Q2	$777K	Buy	+14,000	New	+$882K	0.33%	58
2015 Q3	–	Sell	-24,000	Closed	-$2.88M	–	60
2015 Q2	$2.88M	Buy	24,000 +18,500	+336%	+$2.21M	1.3%	34
2015 Q1	$574K	Buy	+5,500	New	+$557K	0.38%	58
2014 Q3	–	Sell	-20,000	Closed	-$1.26M	–	66
2014 Q2	$1.26M	Buy	+20,000	New	+$1.19M	1.03%	41

Other funds holding ALNY

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

Capital World Investors Los Angeles, California $846B AUM 46.74% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Capital Research Global Investors Los Angeles, California $717B AUM 35.42% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

T. Rowe Price Investment Management Baltimore, Maryland $153B AUM 38.14% 1-Year Est. Return

Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return

State Street Boston, Massachusetts $3.38T AUM 44.17% 1-Year Est. Return

Atika Capital Management's ALNY Position: Q1 2026 in Review

Atika Capital Management sold out of Alnylam Pharmaceuticals (ALNY) in Q1 2026, closing a stake of 10,339 shares — an estimated $4.11M sold.

Atika Capital Management first reported a position in ALNY in Q2 2014 and held it in 15 quarters. The position peaked at $12.1M in Q3 2021. 793 funds tracked by Wall St. Rank hold ALNY as of Q1 2026.

Atika Capital Management reported no remaining Alnylam Pharmaceuticals position as of Q1 2026 after selling out during the quarter.
Atika Capital Management sold 10,339 Alnylam Pharmaceuticals shares in Q1 2026, an estimated $4.11M.
Atika Capital Management first reported a position in Alnylam Pharmaceuticals in Q2 2014 and held it in 15 quarters.
Atika Capital Management's Alnylam Pharmaceuticals position peaked at $12.1M in Q3 2021.
793 funds tracked by Wall St. Rank held Alnylam Pharmaceuticals as of Q1 2026.

Based on Atika Capital Management's 13F filing for Q1 2026, filed 14 May 2026.