Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Southern Union (NYSE: SUG) jumped 17% today when Williams (NYSE: WMB) made a bid to buy the company.

So what: Williams bid of $4.9 billion, or $39 per share, topped an existing bid from Energy Transfer Equity (NYSE: ETE) to buy the company for $4.2 billion, or $33 per share. With Southern Union’s shares now trading near $40 per share, investors are betting a bidding war will erupt, sending shares higher.

Now what: The question really becomes: What if Energy Transfer Equity makes a bid to top Williams’ price? Betting on buyout offers like that is risky business, but the backstop of $39 per share wouldn’t result in too much downside if another offer doesn’t come through. I’m not buying today, and I’d wait this one out if I owned shares, because the possibility of another bump could lead to an even bigger payday.

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