EC
MREO

EcoR1 Capital’s Mereo BioPharma MREO Stock Holding History

EcoR1 Capital’s Portfolio MREO Stock Details MREO Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$318K Sell
1,000,000
-12,368,855
-93% -$3.71M 0.02% 31
2026
Q1 		$4.41M Buy
13,368,855
+5,512,389
+70% +$2.37M 0.19% 24
2025
Q4 		$3.27M Buy
+7,856,466
New +$15M 0.15% 27

Other funds holding MREO

RCMNY
Rubric Capital Management (New York) New York $10.9B AUM 70.31% 1-Year Est. Return
6CM
683 Capital Management New York $2.04B AUM 94.26% 1-Year Est. Return
Bank of America
Bank of America Charlotte, North Carolina $1.55T AUM 33.47% 1-Year Est. Return
DCM
Defilade Capital Management Emeryville, California $747M AUM
NM
Newtyn Management New York $801M AUM 23.14% 1-Year Est. Return
TC
Tejara Capital London, United Kingdom $243M AUM 9.84% 1-Year Est. Return
UBS Group
UBS Group Zurich, Switzerland $786B AUM 40.34% 1-Year Est. Return
Two Sigma Investments
Two Sigma Investments New York $138B AUM 41.87% 1-Year Est. Return
Jane Street
Jane Street New York $1.21T AUM 78.12% 1-Year Est. Return
II
Ishara Investments Los Angeles, California $136M AUM

EcoR1 Capital's MREO Position: Q2 2026 in Review

EcoR1 Capital reduced its Mereo BioPharma (MREO) stake by 93% in Q2 2026, selling an estimated $3.71M and leaving 1,000,000 shares worth $318K. The position accounts for 0.02% of the portfolio, ranked #31.

EcoR1 Capital first reported a position in MREO in Q4 2025 and has held it in 3 quarters since. The position peaked at $4.41M in Q1 2026. 61 funds tracked by Wall St. Rank hold MREO as of Q2 2026.

  • EcoR1 Capital held 1,000,000 shares of Mereo BioPharma worth $318K as of Q2 2026.
  • EcoR1 Capital sold 12,368,855 Mereo BioPharma shares in Q2 2026, an estimated $3.71M.
  • Mereo BioPharma made up 0.02% of EcoR1 Capital's portfolio in Q2 2026, its #31 holding.
  • EcoR1 Capital first reported a position in Mereo BioPharma in Q4 2025 and has held it in 3 quarters since.
  • EcoR1 Capital's Mereo BioPharma position peaked at $4.41M in Q1 2026.
  • 61 funds tracked by Wall St. Rank held Mereo BioPharma as of Q2 2026.

Based on EcoR1 Capital's 13F filing for Q2 2026, filed 14 Aug 2026.