Mereo BioPharma MREO Institutional Ownership

Updated Oct 11, 2026

Mereo BioPharma Group plc (NASDAQ:MREO) counted 62 institutional investors among its 13F-reported shareholders for the quarter ended June 30, 2026.

• Collectively, these holders controlled 35.45% of Mereo BioPharma's outstanding shares in Q2 2026, down from 47.23% in Q1 2026.
• Total shares held in Mereo BioPharma fell 24.89% from Q1 2026, while the number of holders fell 26.19% from Q2 2025.
• Among the 62 holders of Mereo BioPharma, 30 added to their positions, 12 reduced their stakes and 20 left their positions unchanged.
• The aggregate institutional position in Mereo BioPharma was 56.61Mn shares at the end of Q2 2026, down 18.77Mn from the prior quarter and down 40.59Mn from a year earlier.
• Rubric Capital Management LP was the top holder of Mereo BioPharma as of June 30, 2026, with 15.31Mn shares, or 9.59% of shares outstanding.
• The biggest increases in MREO positions during Q2 2026 came from Two Sigma Investments, LP (+1.13Mn shares), Jane Street Group, LLC (+634.97K shares), XTX Topco Ltd (+90.01K shares), JPMorgan Chase & Co (+36.68K shares) and Virtu Financial LLC (+24.83K shares).
• Among holders that kept a stake in Mereo BioPharma, the biggest sellers in Q2 2026 were EcoR1 Capital, LLC (-12.37Mn shares), Newtyn Management, LLC (-4.08Mn shares), Marshall Wace, LLP (-507.1K shares), BlackRock, Inc. (-233.31K shares) and 683 Capital Management, LLC (-222.14K shares).
• According to Business Quant data, the leading holders of MREO for Q2 2026 were Rubric Capital Management LP (15.31Mn shares), 683 Capital Management, LLC (11.78Mn shares), Bank of America Corp (8.2Mn shares), Defilade Capital Management, L.P. (7.56Mn shares), Newtyn Management, LLC (3Mn shares), Tejara Capital Ltd (2.04Mn shares), UBS Group AG (1.45Mn shares), Two Sigma Investments, LP (1.32Mn shares), EcoR1 Capital, LLC (1Mn shares) and Jane Street Group, LLC (774.94K shares).