RA Capital Management (RA Capital) is a multi-stage investment manager based in Boston, MA, USA, focused on healthcare, biotechnology, life sciences, and planetary health companies across early venture through public markets. It deploys capital into private companies at a wide range of stages — from seed and growth rounds to later financings — and includes venture, crossover, and public equity investments.

Pre-Seed: RA Capital can invest earliest seed rounds and even help form companies through its RAVen incubator.
Seed: Active seed investor in biotech/life sciences startups.
Series A–C and Later: Participates widely in Series A, B, C, and later financings, including PIPEs and crossover financings before IPO.

Typical Check Size: Varies substantially depending on stage — can be mid-seven figures to tens/hundreds of millions in growth/crossover financings.
Typical Ownership Taken: Highly variable and not fixed; RA Capital has been documented owning single-digit to double-digit stakes in private/public companies. For example:
• ~9.99% ownership reported in Adicet Bio.
• ~40.6% ownership reported in Artiva Biotherapeutics (public).
• Other positions in private companies can range broadly depending on round size, lead role, and negotiation.
Equity Style: RA Capital often takes significant minority or controlling stakes in companies it backs, especially in biotech where deep conviction is present.
Board/Governance: When ownership is large, RA Capital may take board seats or significant influence; when smaller, influence is commensurate with stake. (Inferred from reported positions and governance practice.)

Submission Method: RA Capital does not publicly list an open portal for startup submissions; engagement is typically via warm introductions, scientific networks, or venture syndicates.
Lead or Co-Invest: RA Capital can lead, co-lead, or participate in private financings; it explicitly states it can participate at any stage and in any role. 

https://www.linkedin.com/company/raven-ra-ventures/

Sector Focus: Primarily clinical biotech, therapeutics, medical devices, diagnostics, life sciences platforms, and related areas where evidence-based science can create major value.
Geography: Global investments, strong presence in U.S. and international life sciences ecosystems.
Stage: Flexible across seed to late private rounds and crossover/public financings. 
Company Profile: Science-driven companies with strong IP, clinical programs, or platform technology. 
Team: Founders and management teams with scientific, clinical, and commercial expertise. 

Initial Screening: Scientific and clinical evaluation given the firm’s deep research capabilities (TechAtlas in-house platform). 
 Partner Review: Engagement with management teams and deep diligence on technology, trials, IP, and regulatory pathways. 
 Deal Structuring: Term negotiation reflects stage and conviction; RA Capital may take material positions reflective of its confidence in value creation. 

Strategic Capital: Large sums of capital capable of supporting clinical trials, regulatory milestones, and commercial scaling.
 Scientific Support: Access to RA Capital’s in-house research tools (TechAtlas) and sector expertise.
 Network: Connections to other institutional investors, Pharma/Biotech partners, and strategic acquirers.
 Governance & Influence: Significant positions often come with board or advisory engagement when appropriate.