Stupidity is contagious. It gets us all from time to time. Even respectable companies can catch it. As I do every week, let's take a look at five dumb financial events this week that may make your head spin.

1. He went Hathaway
The typically squeaky-clean folks at Berkshire Hathaway (NYSE: BRK-A) (NYSE: BRK-B) have fallen into the muck.

David Sokol -- the Berkshire executive that was on nearly everybody's shortlist as Warren Buffett's heir apparent -- resigned this week under a cloud of controversy.

Sokol bought 100,000 shares in Lubrizol, apparently around the same time that he was pitching the specialty chemicals giant as an acquisition target to Buffett. Berkshire Hathaway went on to acquire Lubrizol at a healthy premium a couple months later.

This may not be illegal, but it's ethically gray. Resigning is one way to nip the controversy in the bud, but investors have a right to be concerned about the iconic holding company's succession strategy.

There won't be another Buffett, and he's not getting any younger.

2. I guess that why they're called underwriters
China's Qihoo 360 (Nasdaq: QIHU) was a scorching hot IPO on Wednesday. Underwriters priced the offering at $14.50, but it wasn't enough. Qihoo shares opened at $27 before closing at $34.

I have nothing but good things to say about Qihoo. Its Web browser is second only to Internet Explorer in terms of popularity in China. A free browser is a tough nut to monetize, but Qihoo has used its tech cred to roll out antivirus software, online games, and other services. Revenue climbed 79% to $58 million last year, with profits more than doubling.

If Qihoo's the real deal and the market's buzzing, why is this on the "dumb" list? Well, once again, a Chinese dot-com darling gets hosed by stateside underwriters. Was $14.50 a stub really all that the underwriters could manage when Mr. Market was willing to pay twice as much? If so, popular Chinese companies need to find a way to market their IPOs directly to the first-day investors. Qihoo investors may be pumped about Wednesday's pop, but the company itself left a lot of money on the table in the underpriced deal.

3. Satellites on retainer
One component of a class-action complaint against Sirius XM Radio (Nasdaq: SIRI) has been cleared by a U.S. District judge to proceed.

The alleged consumer-protection violations have been decertified. The remaining case involves antitrust issues. Really? Didn't regulators approve the merger between Sirius and XM because they felt the deal wasn't monopolistic? They took more than a year to clear the corporate combination, so it's not as if they simply skimmed the surface.

Sirius XM merged in 2008, and this claim was originally filed in 2009. Alternatives to satellite radio are even more readily accessible today. It's in Sirius XM's best interests to get this resolved quickly, all the same. We're now just months away from the end of the regulator-mandated three-year freeze on basic plan rates. The open-ended potential of Sirius XM 2.0 will also poke its head later this year. Legal uncertainties are the last thing a company that is starting to come into its own needs.

4. Principle over principal
It's been a year since Google (Nasdaq: GOOG) staged a partial retreat out of China, and it continues to pay the price.

SINA (Nasdaq: SINA) is nixing Big G as the search engine of choice on its popular portal, ending a deal that began four years ago. SINA is hoping to roll with a proprietary platform in Google's place.

Google commanded roughly a third of China's market share in search when it revealed that it would be pulling back from delivering government-censored results on principle. The move may have scored the global search leader some serious karma points, but it continues to lose footing in the world's most populous nation. Chinese traffic tracker Analysys International now has Google remotely serving less than a fifth of the country's search queries.

5. An axiom by any other name
There are many ways for a public company to have a bad week:

  • A CEO can step down on Monday.
  • The CFO can announce his intent to resign in the coming months.
  • The company can announce that it is writing down its struggling international business.
  • Three words: Hosed-down guidance.

What happens when all of these things happen? Ask Acxiom (Nasdaq: ACXM). The marketing specialist got banged up after revealing all of these unwelcome events.

There's always next week, I guess.

Which of these five moves do you think is the dumbest? Share your thoughts in the comment box below.