SAN FRANCISCO — Riley Newman, a former head of data science at Airbnb, set out in mid-2017 to raise a venture capital fund that would invest in a multitude of tech trends.

But he quickly realized that potential investors were not interested in that kind of fund. Instead, all they wanted to hear about were his former Airbnb colleagues and whether they might start their own companies.

“It was, ‘Yeah, all that stuff is fine, but Airbnb, right?’” Mr. Newman, 36, said. “Airbnb was where we had a competitive edge on the market.”

So Mr. Newman and his partners at Wave Capital adjusted their pitch: They said they were creating a fund to invest specifically in Airbnb employees who were planning to leave the company to become entrepreneurs. It worked. He and his partners quickly secured $55 million and now are preparing to make a flood of investments after the $31 billion home rental start-up goes public sometime in the next year and employees cash out their shares.