NEW YORK (TheStreet) -- Messaging app Snapchat's parent company Snap secretly filed for an IPO with the SEC and could go public as early as March with a value of $20 billion to $25 billion, CNBC reports. Companies making less than $1 billion can file for an IPO confidentially to test investor enthusiasm. 

Former CEO of Time Warner's (TWX) CNN Walter Isaacson joined CNBC's "Squawk Alley" Wednesday morning to talk about the potential IPO; he said he was impressed by the company.

Changing its name to Snap this past September is particularly impressive because it gives the company a "much broader" label, rather than just being known as a messaging app where the chats quickly disappear, he said. 

The "ultimate test" for a tech company like Snap is "not just do you have a cool service, but do you have a platform upon which other people can build good products and good services?" Isaacson said. Apple's (AAPL) - Get Report iPhone is "so great" because it became a platform for other innovative products. In the same way, Snap seems willing to let other people use its platform for their own "ingenious ideas." 

Right now investors are trying to decide if the company is more than just a messaging app, Isaacson said. This will largely be determined by the success of Snap's first hardware product, video recording glasses called Spectacles that went on sale last week. 

"Over the next two months, investors are going to get to see, is this a company that can really execute?" he claimed. "And I think it can. It's got great leadership, got a great board. But you know, is it a company that can really execute on great, new product, or is it really just that flash in the pan messenger service? I think it's the former."

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