Online accommodation marketplace Airbnb, Inc. has confirmed that it raised $1.5 billion in private equity funding earlier this year via a U.S. Securities and Exchange Commission (SEC) filing.

The Wall Street Journal first broke the news of the round back in late July after rumors of a new round emerged earlier that same month, but the funding has never been confirmed before now.

Investors in the round are said to include General Atlantic, Hillhouse Capital Group of China, Wellington Management, Baillie Gifford and Tiger Global Management.

It’s believed the new funding was invested on a $25.5 billion valuation, meaning that Airbnb is now the third biggest unicorn (startup with a valuation over $1 billion) by valuation after Xiaomi, Inc. on $45 billion and Uber, Inc.’s $62.5 billion.

Back in June, Airbnb was predicting $900 million in revenue for 2015 (up from $250 million in 2013), but a separate report from The Wall Street Journal on another unconfirmed round of $100 million in November reported that Airbnb generated $340 million of revenue in the third quarter on bookings of $2.2 billion, meaning that the figure could be closer to $1 billion for the year, with 23.8 million nights booked by the service, up from 11.3 million from the same quarter of 2014.

Peak Unicorn

Although we’ve used the phrase previously, it bears mention again: Airbnb is undoubtedly highly successful and has created an amazing business, but it’s worth keeping in mind that it does nothing more than act as a middle man between owners and renters.

Compare and contrast Airbnb, with its, lets say, $1 billion in revenue this year, to hotel group Marriott International, Inc., which manages more than 4,000 hotels and last year had $13.8 billion in revenue and is valued at about $21 billion; this is not to take away from Airbnb’s success, but Marriott actually owns tangible assets, Airbnb owns a website.

Like other unicorns, it should also be noted that Airbnb is not profitable either, with the company predicting that it will break even in 2020; venture capital investments are always about taking risk, but five years is a long time to bet on a company the size and value of Airbnb breaking even as well.

Prior to this new round, Airbnb has raised $798.4 million from investors, including SherpaCapital, TPG Growth, T. Rowe Price, Dragoneer Investment Group, Founders Fund, CrunchFund, Sequoia Capital, Ashton Kutcher, Andreessen Horowitz and others.

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