In hindsight, it’s kind of funny that the big tech bubble debate this week focused on Candy Crush Saga owner King Digital Entertainment’s IPO filing. It’s funny because, on Thursday night, Wall Street priced the craziest deal since the heights of the Internet bubble and almost no one complained a bit.

That deal was for Castlight Health (CSLT), a company that offers health information via the Internet to inform medical choices and reduce insurance costs. Sounds like a pretty good idea, and Castlight says it has helped some of its corporate customers reduce their health costs by more than 10% a year.

Goldman Sachs, Morgan Stanley and other lead underwriters priced Castlight’s shares at $16, above an already raised expected range of $13 to $15, giving the company a valuation of $1.4 billion. That's billion with a “b.” Last year, Castlight had $13 million of total revenue. That’s million, with an “m.”

Then the stock opened on Friday at almost $40, giving it a valuation of over $3 billion!

Insane valuation

Jay Ritter, a professor at the University of Florida and my go-to source on IPOs for the past few decades, tells me that Castlight's insane level of valuation – 107 times revenue (not profits, as they had huge losses last year) – of the original IPO pricing hasn’t been seen for a tech deal since the year 2000, the twilight of the 20th century. Of the prior 13 deals priced at 100 times revenue or more and sales of at least $10 million, the average 3-year return was -92%.

Investors have been attracted by the siren song of market potential. With trillions spent on health care and everyone trying to save money, surely there’s a big market for Castlight’s services?

That’s probably true but it’s also obvious to a lot more folks than those at Castlight. Try the numerous private competitors, companies such as Change Healthcare, backed by investors including Blue Cross Blue Shield, and Healthsparq, which recently said it served 60 million consumers. And the big health insurers themselves, Aetna (AET) and UnitedHealth Group (UNH), for example, are already experimenting with similar services and giving them away free to major customers.

To be sure, it’s a great idea. One of the biggest hurdles to controlling healthcare costs is the complexity and obfuscation in the market. It’s hard to be a smart shopper when you can’t compare the quality of different providers or even know how much they’ll end up charging. Castlight and its competitors collect vast amounts of data and display relevant bits in a more clear and simple way to help consumers make smarter choices.