Siren LLC’s Septerna Inc SEPN Stock Holding History

Siren LLC’s Portfolio SEPN Stock Details SEPN Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	$63.6M	Sell	1,900,000 -100,000	-5%	-$2.84M	1.29%	28
2026 Q1	$48.1M	Hold	2,000,000	–	–	1.33%	22
2025 Q4	$55.8M	Sell	2,000,000 -202,514	-9%	-$4.84M	1.66%	19
2025 Q3	$41.4M	Hold	2,202,514	–	–	1.62%	21
2025 Q2	$23.3M	Hold	2,202,514	–	–	1.2%	27
2025 Q1	$12.8M	Hold	2,202,514	–	–	0.72%	32
2024 Q4	$50.4M	Buy	+2,202,514	New	+$52.1M	2.23%	10

Other funds holding SEPN

RCM

RA Capital Management Boston, Massachusetts $11.5B AUM 168.77% 1-Year Est. Return

TGV

TRV GP V Boston, Massachusetts $498M AUM 267.53% 1-Year Est. Return

DCM

Driehaus Capital Management Chicago, Illinois $17.3B AUM 211.34% 1-Year Est. Return

TGV

TRV GP VI Boston, Massachusetts $232M AUM 247.08% 1-Year Est. Return

Samsara BioCapital Palo Alto, California $1.22B AUM 242.83% 1-Year Est. Return

Goldman Sachs New York $1.15T AUM 47.82% 1-Year Est. Return

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

ACA

Avoro Capital Advisors New York $11.1B AUM 207.82% 1-Year Est. Return

Jupiter Topco New York $245B AUM

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

Siren LLC's SEPN Position: Q2 2026 in Review

Siren LLC reduced its Septerna Inc (SEPN) stake by 5% in Q2 2026, selling an estimated $2.84M and leaving 1,900,000 shares worth $63.6M. The position accounts for 1.29% of the portfolio, ranked #28.

Siren LLC first reported a position in SEPN in Q4 2024 and has held it in 7 quarters since. 154 funds tracked by Wall St. Rank hold SEPN as of Q2 2026.

Siren LLC held 1,900,000 shares of Septerna Inc worth $63.6M as of Q2 2026.
Siren LLC sold 100,000 Septerna Inc shares in Q2 2026, an estimated $2.84M.
Septerna Inc made up 1.29% of Siren LLC's portfolio in Q2 2026, its #28 holding.
Siren LLC first reported a position in Septerna Inc in Q4 2024 and has held it in 7 quarters since.
154 funds tracked by Wall St. Rank held Septerna Inc as of Q2 2026.

Based on Siren LLC's 13F filing for Q2 2026, filed 13 Aug 2026.