As is customary among VCs, Vertex US tries to build relationships with founders in hopes that the startups will agree to let the early-stage firm lead their next round of financing. After recently meeting with one such founder about 30 times and helping the company put together diligence materials, Vertex was sure that they were the frontrunner to lead its Series A.

But at the last minute, a crossover fund stepped in with a proposal at a valuation that was about $40 million more than Vertex was offering. READ MORE