In the 1990s, a tech bubble emerged — and then burst — in the public market. Now, there could be one in the private market, too.

In a new piece for Vanity Fair, Nick Bilton reports on what could burst Silicon Valley’s next tech bubble.

It’s an illuminating story — Bilton talks about overly optimistic venture capitalists pumping money into startups, a culture of FOMO (“fear of missing out”) among investors, and over-inflated valuations.

In part, Bilton says, venture capital investment in recent years has been fuelled by investors chasing unicorns — billion-dollar private tech companies — scared of missing out on funding the next Uber. The valuations commanded by private companies aren’t verified or fact-checked by the SEC or the public market.

Several venture capitalists have made mention of the current state of VC funding in Silicon Valley, noting the crazy amount of money being pumped into startups today. Some — even those with unicorn companies in their portfolios — have said that we’re in a bubble, and it could be close to bursting.

“Arguing we aren’t in a bubble because it’s not as bad as 1999,” Benchmark partner Bill Gurley tweeted last year, “is like saying that Kim Jong-un is fine because he’s not as bad as Hitler.”

Gurley, whose firm’s portfolio includes companies like $US51 billion Uber and $US16 billion Snapchat, has been sounding the alarm about an impending bubble for a while now. In a tweetstorm last month, he said he believes a recent downturn in tech stocks is a sign that Silicon Valley’s golden age could soon be over.

We’re at an “inflection point,” Gurley says, and bad things are happening “quickly.” In other words: winter is coming for Silicon Valley.

In his story for Vanity Fair, Bilton also says that in some cases, startups are over-inflating or even completely fabricating their valuations when talking to investors.

“One successful venture capitalist told me that he recently met with a unicorn that was seeking a new round of funding,” Bilton says. “When he asked the C.E.O. why he had valued his company at $US1 billion, he was told, ‘We need to be worth a billion dollars to be able to recruit new engineers. So we decided that was our valuation.'”

You can read Bilton’s whole report over at Vanity Fair.

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