As cleanup costs mount and with no end in sight to the undersea oil gusher in the gulf, investors have started to take a hard look at the reality at the disaster’s impact on BP (BP). The company has shed more than $70 billion in value since April 20 when an explosion on one of its oil rigs in the Gulf of Mexico sparked the worst crude oil disaster in U.S. history.

Some say that things could get even worse as the blowout on the ocean floor continues to wreak havoc and the price tag continues to mount. But many others say the sell-off is overdone, and that investors would be wise to buy shares at what could be bargain valuations.

Yet another possibility is a buyout by one of BP’s bigger oil rivals – and here’s who would be the most likely suitors:

First up is Exxon Mobil (XOM), which boasts a market size of around $270 billion. As BP’s market cap is now about $115 billion, making it considerably less than corporate titan Exxon. XOM just made a huge purchase of natural gas stock XTO energy, with a buyout worth $41 billion announced at the end of 2009. That makes a BP buyout tricky with all that cash tied up, but also proves that Exxon has the means to make a huge buyout if its leadership thinks its in the company’s best interest.

• Related Article: Exxon Mobil - 5 Reasons to Sell XOM Stock

Another possible suitor is Chevron (CVX), though this stock is a bit less likely. CVX stock smaller, with a market cap of about $145 billion at current valuation. Even at BP’s beaten down pricing it would take quite a leveraged bet for Chevron to acquire the oil stock’s operations in a buyout. And such a move would expose Chevron to significant losses if liabilities remained a problem due to continued flow of oil in the Gulf or consumer backlash. Besides, BP crude oil estimates from the disaster are slippery and it may be impossible to know the true extent and cost of the damage for months or even years. However, BP’s core business is strong and Chevron would benefit from gobbling up a once-larger rival to expand its reach.

• For even more potential buyers of BP stock, including China and Brazil oil stocks, click here!
  

True, any buyout talk right now is simply speculation. There are no plans, formal or informal, for any rivals to take over BP and even though the company has lost a huge portion of its market cap it is still one of the Wall Street heavyweights.

But that’s not to say buyout talk won’t eventually step outside of speculation and into serious discussions. Just as no one would have imagined a BP buyout earlier in the year, who would have imagined that the oil spill six weeks ago would continue unabated this long? At the rate of decline that this crude oil stock has seen, it’s not outside the realm of possibility that a company could sweep in with a buyout offer if BP stock troubles continue to mount. Even Conoco Phillips (COP), one of the “smaller” oil stocks with a market cap of $76 billion, may eventually become a likely suitor if BP continues its rapid downward spiral. 

Even with the liability of the gulf oil spill, a deep discount on BP compared with its value just a few months ago may be too much for a buyer like Exxon or Chevron to pass up.

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