Before Clearview Became a Police Tool, It Was a Secret Plaything of the Rich

“I have the app,” Mr. Lambert said in an interview. “I’ve used it to talk about what we’re doing in the space. I show it to friends of mine, potential investors.

“They thought it was amazing,” he added. “They say, ‘How do I get that?’ And I say, ‘You can’t.’”

Mr. Scalzo, the founder of the investment firm Kirenaga Partners, said in an interview that his two daughters, who are in “grade school and junior high,” enjoyed playing with the app.

“They like to use it on themselves and their friends to see who they look like in the world,” he said. “It’s kind of fun for people.”

A spokesman for Mr. Thiel did not respond to a request for comment.

When Clearview was seeking its Series A round of funding, which was completed in 2019, the start-up contacted a number of venture capital firms, including Sequoia Capital and Khosla Ventures. Access to the app was offered as a perk, according to people familiar with the company’s fund-raising attempts.

Doug Leone, a billionaire partner at Sequoia, was given a login, according to three people with knowledge of Clearview’s operations. But his account was revoked when Sequoia declined to invest. A spokeswoman for Sequoia declined to comment.

In September, Ashton Kutcher, the actor turned venture capitalist, described an app much like Clearview during a YouTube series called “Hot Ones,” in which guests are interviewed while eating spicy chicken wings.

“I have an app in my phone in my pocket right now. It’s like a beta app,” Mr. Kutcher said. “It’s a facial recognition app. I can hold it up to anybody’s face here and, like, find exactly who you are, what internet accounts you’re on, what they look like. It’s terrifying.”