Series Bとは何ですか？

A Series B round is raised once a company has proven its business model and is ready to scale operations, expand into new markets, or build the organizational infrastructure needed to support sustained growth. By this stage, the company has moved beyond existential questions about whether the product works or whether customers will pay — Series B is about how fast you can grow and how efficiently you can do it. Round sizes typically range from $20M to $80M or more, with pre-money valuations generally falling between $40M and $200M, depending heavily on sector, growth rate, and market.

Series B investors are typically growth-stage venture capital funds — firms like Bessemer Venture Partners, General Catalyst, or Insight Partners — that specialize in scaling companies rather than incubating them. Due diligence at this stage is significantly more rigorous than in earlier rounds: investors will examine unit economics in detail (CAC, LTV, payback period, net dollar retention), financial model assumptions, competitive dynamics, organizational design, and the quality of the management team at scale. They want to understand not just whether the company is growing but whether the underlying business becomes more efficient as it grows.

The capital from a Series B is typically deployed across sales and marketing (scaling a repeatable go-to-market motion), engineering and product (building the infrastructure for 10x scale), and team (hiring senior functional leaders in finance, operations, people, and GTM functions). It is also common for a portion of the round to provide secondary liquidity to early employees and founders, though this is negotiated case by case.

Series B terms are more complex than earlier rounds. Investors will negotiate liquidation preference stacks, anti-dilution protection, board representation, and information rights with greater sophistication. The cap table at this stage has meaningful complexity — SAFEs have converted, Series A preferred shares are outstanding, and the new Series B terms must be layered in carefully.