What a basketcase: Groupon has slashed its proposed valuation to $12 billion from $30 billion as it ramps up for an initial public offering. So if you're in the market for a technically insolvent online discounter with shady accounting, now is the time to buy! Goldman Sachs is involved, so you just know it's a good deal.

Now is a bad time to go public. Two companies have cancelled their IPOs this week alone. So why is Groupon slashing its valuation and pressing forward anyway? Probably because it owes more than it has in the bank, having paid out a staggering percentage of its venture capital in bonuses, and it's losing money every quarter. New York Times business columnist Andrew Ross Sorkin is asking why lead underwriters like Goldman Sachs—whose CEO personally sought Groupon's business—didn't blow the whistle:

It [is] not fully explain[ed] how Groupon's underwriters, whose endorsement of the company is supposed to be considered the Good Housekeeping Seal of Approval, originally came up with Groupon's questionable $30 billion valuation... The cynical reason that the banks stood by Groupon and its accounting shenanigans is most likely the expected fees from the offering. Even if Groupon's I.P.O. values the company at $10 billion instead of $30 billion, the banks will probably walk away with hundreds of millions of dollars.

Goldman Sachs, screwing investors to line its own pockets? Come on.

[Photo of Groupon CEO Andrew Mason via TechCrunch/Flickr]