Apple Tree Partners

Seth Harrison, founder and managing partner, leads investment decisions and serves on the boards of all portfolio companies created within ATP's current fund. Harrison has invested in life sciences since 1991, previously as a general partner at Oak Investment Partners. He is supported by partners Anna Batarina and venture partners including Paul Da Silva Jardine and Spiros Liras, who bring decades of pharmaceutical R&D leadership.

ATP primarily creates companies rather than sourcing them externally. The firm works with scientists on pre-IP ideas and spins out assets from existing portfolio company pipelines. Venture partners with deep pharmaceutical discovery backgrounds — several formerly at Pfizer, Amgen, and Novartis — identify and shape programs internally before forming standalone entities around them.

ATP invests directly in companies it creates or builds, providing flexible capital from seed stage through IPO and beyond. There is no evidence the firm makes LP commitments to other venture funds. Its model centers on company creation, strategic incubation, and long-term equity ownership.

ATP covers the full spectrum: from pre-IP ideas and seed-stage startups to growth rounds and public-company holdings. The firm explicitly states it invests 'from seed stage through IPO and beyond,' and supports portfolio companies in strategic transactions and business combinations.

ATP focuses exclusively on life sciences — drug discovery, medical devices, and digital health. The firm does not invest in general technology, consumer, financial services, or industrial sectors. Its website, portfolio, and team composition reflect a single-sector commitment to therapeutics and healthcare innovation.

ATP operates as a venture capital firm with a venture-partner model. Seth Harrison's network of venture partners — typically former research heads from major pharmaceutical companies — provide scientific and operational expertise. The firm also maintains in-house functions including legal, communications, talent, and new product planning to support portfolio companies.

ATP engages in collaborations with pharmaceutical partners — for example, a $1.1B partnership between Aileron Therapeutics and Roche, and a 2025 Novo Nordisk collaboration with Deep Apple Therapeutics. The firm's model also supports co-investment alongside other life-sciences VCs, as seen when Galvanize Therapeutics raised an oversubscribed Series C round in 2025.