As prices became untethered from reality, the Nasdaq index doubled in value between 1999 and 2000 without “any plausible candidate for fundamental news to support such a large revaluation,” as the economists J. Bradford DeLong and Konstantin Magin wrote in a paper on the bubble. The crash was equally swift and arbitrary. Between February 2000 and February 2002, the NASDAQ lost three-quarters of its value “again without substantial negative fundamental news,” DeLong and Magin wrote. By late 2000, more than $5 trillion in wealth had been wiped out. This sudden rise and sudden collapse in asset prices—without much change in information about the underlying assets—is the very definition of a bubble.

The current situation is different, in at least two important ways.

First, in the dot-com bubble, public investors got hosed. Today, it’s public investors that are doing the hosing.

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When the web browser Netscape went public on August 9, 1995—the day many cite as the beginning of the dot-com bubble—its stock skyrocketed from $28 to $75 in a matter of hours, even though the company wasn’t profitable. In today’s market, the opposite is happening: Unicorns with no positive earnings are getting slaughtered at the gates. WeWork’s valuation fell more than 80 percent pre-IPO when investors balked at its mounting losses. Peloton, Lyft, and Uber have also struggled to persuade public markets to grade them on a curve; all saw their stock prices fall on the day of the public offering. Institutions and retail investors are refusing to fork over to unicorns the valuations that private investors were expecting—particularly Softbank, a major backer of Uber, DoorDash, and WeWork.

This isn’t a picture of mass mania. It’s a picture of public sobriety, where the masses are diagnosing an acute fever in private markets.

Second, there is little sign of a crisis for firms whose main product is pure software.

Judging from the news, you might think this has been a terrible year for technology companies. But tech IPOs have been strong for the past two years, “as long as what you’re buying is actually a real tech company,” JP Morgan’s chair of market and investment strategy, Michael Cembalest, wrote in an October 7 research note. By “real tech,” Cembalest was referring to companies whose principal product is software, rather than, say, WeWork, which is in truth a real-estate company caught wearing an Actual Tech Company costume before Halloween.

You might not have heard about these “real tech” companies—like Zscaler, Anaplan, and Smartsheet—because they mostly sell business-to-business software or cloud services. But all of them are trading more than 100 percent above their listed IPO price. The problematic firms, Cemablest wrote, are those that aren’t pure tech. Either they sell hardware plus software (like the stationary-bike company Peloton) or they own a digital marketplace for humans to transact goods and services in the physical world, like Uber, Fiverr, and Lyft. All those companies are trading below their IPO price.