Marc Benioff had a stake in Quip before Salesforce bought it for $750 million

Over the summer, Salesforce bought a tiny startup called Quip, a productivity app founded by Facebook's former CTO, Bret Taylor, for a reported $750 million.

Benioff was convinced to buy Quip for that price to get Taylor to come work for him, the official story goes.

"He's one of the absolute rising stars of our industry," Benioff told Business Insider. "It's been my dream to work more closely with Bret Taylor."

Benioff has known Taylor for a good five years, from when Benioff first started hosting a private monthly dinner at his home for startup CEOs and the tech elite. These dinners have included guests like Yahoo CEO Marissa Mayer and Dropbox CEO Drew Houston. Over the years, Benioff grew increasingly impressed by Taylor and his long list of accomplishments from helping to create Google Maps to the Facebook Like button.

Benioff was also apparently impressed with Quip. He was an angel investor in the company, the CEO told attendees at the Intel Capital Global Summit on Tuesday.

That's not unusual. Benioff is known as a very active angel investor who has invested in nearly 200 startups, he said. Although he does not vet every detail of every deal himself personally - he has a private fund, managed by "a friend of mine," he said.

To avoid potential conflicts of interest, he runs all of his potential investments by the Salesforce board to get their ok in advance.

"As a public CEO, anytime I make an investment it has to get cleared by my board. That's just part of the process," he said.

When the conflict arose with Quip, he gave his stake away, Benioff explained (emphasis ours):

"Occasionally, I end up in a company where I have some small position, because I was an angel, and Salesforce is looking to acquire that company and I'll either try to divest before the acquisition. Like in the example of Quip. I gave all my stock to UCSF before Salesforce bought the company. Or I fully disclose it in the transaction. But these numbers have been very small."

UCSF, the University of California San Francisco medical center and affiliated med school, is Benioff's top priority charity. He's donated $200 million to help UCSF build two children's hospitals in the Bay Area, and does a lot of ongoing fund raising for it.