Several years ago, venture capitalist Stewart Alsop gave a speech about why Facebook shouldn’t have accepted Microsoft’s investment at a $15 billion valuation. Or, more specifically, why Facebook shouldn’t have allowed the valuation to leak. His argument was that Facebook would likely go public or be acquired at a lower number, and the subsequent press would make the company appear to be on the decline – even though $5 billion or $10 billion would have been a massive win for a company at that stage of its development.

To be sure, Stewart was wrong about Facebook. But his lesson might be taking hold at Groupon. I don’t know who reported it first, but for months it’s been publicly suggested that Groupon is seeking a post-IPO valuation of $25 billion. You can’t figure that out from the available SEC docs, so clearly this was leaked by someone either at Groupon or someone else (read: banker) who met with company executives.

If Groupon itself was the hubristic leaker, then it deserves many of the arrows currently sticking out of its North Side hide. And if it was someone else, then Andrew Mason should track that person down and shove him into a dollhouse miniature.

For all of its issues, including those with the SEC, Groupon is a revenue-producing monster that almost certainly will price an IPO later this year. But now anything short of $25 billion – and it almost certainly will be short of that – will be viewed as some sort of embarrassment or loss of momentum. Not because a $10 or $15 billion valuation actually is embarrassing for an unprofitable company founded three years ago, but because of a perception it or someone else needlessly created. At the very least, it hopefully will be a cautionary tale for anyone who follows.

[Caveat: If Groupon goes public at a valuation lower than $6 billion – i.e., the price Google offered to pay for an acquisition last year – then the embarrassment would be legitimate.]

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