Series A / B / C Funding
Sequential rounds of venture capital financing, each typically larger and at a higher valuation than the previous.
Definition
Startup funding follows a conventional progression: pre-seed and seed rounds (early-stage, small amounts, validating the concept), Series A (first major VC round, typically $5-30M, after product-market fit), Series B (scaling operations, $20-100M), Series C and beyond (major expansion, international growth, often $100M+).
AI companies have received historically large rounds at each stage due to the capital intensity of frontier model training. Anthropic raised a $7.3B Series C; Inflection AI raised $1.3B at Series B stage; many Series A rounds for AI startups now exceed $50M. Later rounds often involve strategic investors (Microsoft → OpenAI, Google → Anthropic) alongside financial VCs.
The round letter becomes less meaningful at later stages — some companies skip letters or use other designations. "Growth equity" and "late-stage VC" often describe rounds above $200M. At some point, companies may pursue an IPO, SPAC, or remain private indefinitely ("unicorn permanence").
Examples
- Anthropic $7.3B Series C
- OpenAI $10B Microsoft investment
- Mistral AI €385M Series B