Stripe becomes the third-highest-valued U.S. startup

Investors: Return backers include Sequoia Capital, General Catalyst and Andreessen Horowitz.

• This round is not yet closed, as the company remains in discussions with new investors. Stripe co-founder and president John Collison declined to say if the entire $250 million is spoken for by insiders, who then would cut back their allocations for newbies, or if some of it still needs to be filled.

The bottom line: "Investors view payments companies like Stripe as a way to get exposure to a basket of fast-growing public and private tech companies, since Stripe’s revenues are tied to its customers’ growth. The market for payments services is also expanding as more commerce moves away from physical stores and toward digital storefronts," writes the Wall Street Journal's Peter Rudegeair.

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