Do I need a business plan for the start-up founder card, and what must it show?

A business plan is a required document, not an optional extra. The official source states you must submit a consistent business plan for establishing and running the company, and the venture must be innovative in its products, services or technologies.

The plan should align with your capital evidence, ownership share and your role as someone exercising controlling influence over management. Treat it as a central part of the application: it supports both the innovation requirement and your credibility as a founder. Where an incubator is involved, referencing that admission can also strengthen your case and add bonus points.