September 2025 Recap

OWL’s Biotech group had the strongest performance in September. After a tough start to the year, the disclosed holdings of the group have risen nearly 40% over the past 4 months. As noted in our July recap and below, returns have been partially driven by a few companies with positive clinical trial results, as well as the overall strength in the sector. Energy and Cyclicals also had a strong month in September, and Europe was the biggest underperformer for the month.

As a reminder, the table below is based on our “OWL Groups” – curated lists of over 500 managers frequently found in leading allocators’ portfolios. These lists are categorized by geography, sector, and style, enabling our users to easily monitor groups of managers and their underlying disclosed holdings. All returns shown are estimates based on publicly disclosed holdings.  

Outperforming Biotech Managers

In July, we highlighted the outsized impact that an 8x return for Abivax had on biotech managers. There were several big stock winners again this month - most notably uniQure (+257%), Cidara Therapeutics (+52%), and Merus (+41%) - with beneficiaries including Vestal Point, Stempoint, EcoR1, Ikarian, TCG Crossover, Paradigm Biocapital, and Integral Health.

Slate Path

For our users, last Friday’s newsletter included a list of managers that had the best and worst performance in September. One of September’s top performers was David Greenspan’s Slate Path, which we originally profiled last year. Over the past decade, Slate Path’s disclosed holdings have consistently outperformed, ranking among the top 10 managers tracked by OWL:

The firm’s September results were driven by strong gains in several of its largest positions, including Western Digital (up 49% in September), Seagate (up 41%), Sandisk (up 116%), and Nebius (up 64%). According to OWL estimates, these four holdings are the most profitable in the firm’s history, together generating nearly $2 billion in profits to date.

2025 has been a particularly strong year for Slate Path: we estimate that more than 40% of the firm’s cumulative profits earned on long positions have been generated this year alone:

As a reminder, OWL users can access analytics, including estimated P&L by position, cumulative P&L, and sizing skill for thousands of managers with disclosed public equity positions.

Slate Path, which now manages $8.4 billion, counts UTIMCO and several other large allocators among its LPs (OWL users can see the full list on the platform). UTIMCO was a day one investor in October 2012 and disclosed a 15% IRR for the fund as of 12/31/24, the second highest in its entire hedge fund portfolio.

Other News/Events

• Hedge-Fund Stars Are Making So Much Now That They Are Hiring Agents

• Interview with Dave Morehead, Baylor CIO

• U.S. family offices dominate pay race with $1 million CIO salaries

• LA Pension Funds to Host Emerging Manager Event

• Brown and Northwestern Endowments Turn to Secondary Markets

• Heinz’s McCall Cravens on the Importance of Manager Selection

• Japan Activist Investor Yoshiaki Murakami Revives Push For Higher Stock Prices

• Facebook Made Him A Billionaire. Now This Venture Capitalist Is Back With Another Grand Slam

• Citadel expands US footprint in Boston

• Eisler to Shut Hedge Fund Amid Talent War and Poor Returns

• University of Pennsylvania Reports 12.2% FY Return

• Duke Reports 9% FY Return

• Arizona State University Foundation reports 7.8% FY return

• U of Illinois Reports 10.2% FY Return

• U of South Carolina Reports 12.8% FY Return

• Cleveland Clinic hiring Investment Analyst

About Old Well Labs

OWL is an intelligence platform built for allocators, by allocators. Leading endowments, foundations, and family offices use the system to find, monitor, and connect with thousands of fund managers globally. OWL's analytics engine has collected over one billion data points from 65 countries. We make it easy for allocators to find and track information about the managers they care about – not just positions but also performance analytics, people data, business information, and details about the manager investments of other allocators.

Disclaimers

Returns represent the return on invested capital of publicly disclosed long positions, as calculated by OWL. Actual returns may vary based on a number of factors, including (but not limited to) undisclosed positions, short exposure, non-equity holdings, cash holdings, and lagged disclosure of positions.

This newsletter and the material on the Old Well Labs platform are for informational purposes only and should not be considered investment advice or a recommendation of any particular security, manager, or strategy. Old Well Labs shall not be liable for any investment gain or loss that may occur from the use of this material. No part of this material may be reproduced in any form or used in any publication without express written permission from Old Well Labs.