EBay chief John Donahoe says he sees bitcoin and other digital currencies playing an "important role" in PayPal, the e-commerce giant's Internet payment platform.

"We're going to have to integrate digital currencies in our wallet," Donahoe said in an interview on CNBC's "Squawk Box."

While refusing to say when, the eBay CEO talked broadly about the advantages of bitcoin and why he owns some. "I'm not buying it as an investment. I'm buying it to understand how it can be used."

"I think there are two sides of it, the investment side and the digital currency side," he continued in the interview, which aired Thursday. "I'm more interested in the digital currency side about how you and I can exchange value seamlessly using technology."

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