Greenhaven Road Capital’s Investment in AnaptysBio

In its Q2 2026 investor letter, Greenhaven Road Capital highlighted AnaptysBio, Inc. (NASDAQ:ANAB) as a newly added position. The investment management company emphasized that AnaptysBio, Inc. (NASDAQ:ANAB) is a clinical-stage biotechnology company focusing on immunology therapeutics for autoimmune and inflammatory diseases.

AnaptysBio, Inc. (NASDAQ:ANAB) has been gaining significant attention in the market, with its shares closing at $58.47 per share on August 14, 2026, reflecting a market capitalization of $1.73 billion. The company’s one-month return stood at 16.27%, while its shares gained 338.15% over the past 52 weeks.

Greenhaven Road Capital stated in its Q2 2026 investor letter that AnaptysBio, Inc. (NASDAQ:ANAB) is a drug royalty company. In 2014, Tesaro licensed a portfolio of pre-clinical antibodies from AnaptysBio. Tesaro, then a small company with $180M in cash, paid AnaptysBio $17M under an agreement designed for two small companies.

The agreement included exclusivity and notification provisions and required Tesaro to seek an ‘optimal commercial return’ for AnaptysBio’s drugs, which were still in clinical trials. Five years later, in 2019, GlaxoSmithKline acquired Tesaro. In 2021, AnaptysBio’s cancer drug Jemperli was approved. Five years after that, GSK spent $10.6B to acquire Nuvalent and their cancer portfolio.

This year, Jemperli will generate more than $1B of revenue for GSK. Jemperli royalties drive virtually all of AnaptysBio’s business, but the drug represents less than 5% of GSK’s revenue and a declining share of their oncology portfolio as GSK continues investing in new drugs.

Greenhaven Road Capital’s investment in AnaptysBio, Inc. (NASDAQ:ANAB) is an interesting development, especially considering the company’s unique business model. AnaptysBio, Inc. (NASDAQ:ANAB) is not on our list of 40 Most Popular Stocks Among Hedge Funds Heading Into 2026. According to our database, 33 hedge fund portfolios held AnaptysBio, Inc. (NASDAQ:ANAB) at the end of the first quarter, up from 29 in the previous quarter.

While we acknowledge the potential of AnaptysBio, Inc. (NASDAQ:ANAB) as an investment, we believe certain AI stocks offer greater upside potential and carry less downside risk. If you’re looking for an extremely undervalued AI stock that also stands to benefit significantly from Trump-era tariffs and the onshoring trend, see our free report on the best short-term AI stock.

In another article, we covered AnaptysBio, Inc. (NASDAQ:ANAB) and shared Laughing Water Capital’s insight on the company. In addition, please check out our hedge fund investor letters Q2 2026 page for more investor letters from hedge funds and other leading investors.