Midwest Air Group (NYSE: MEH) agreed last week to be acquired by TPG Capital, and CEO Tim Hoeksema relieved investors concerned about its independence by proclaiming, "The cookies stay." The move closed the door on AirTran's (NYSE: AAI) two-year hostile takeover attempt, but reports have now emerged that could allow Northwest (NYSE: NWA), the "passive investor" in the acquisition, to actually own Midwest outright one day.

TPG partner Richard Schifter is quoted by The Associated Press saying "The equity firm may want to cash out of the deal some day, and Minneapolis-based Northwest could become the sole owner." Schifter told the Kansas City Business Journal that a potential acquisition of Midwest by Northwest would be "several years out and isn't anything we expect in the near future."

The potential for Northwest to acquire Midwest one day has definitely ruffled some feathers in the region. The Milwaukee Journal Sentinel said in an editorial that TPG's recent conference call with reporters was "not encouraging" and that questions remain, including if Midwest could survive in the business. The Journal also questioned how "passive" Northwest's relationship with Midwest will be in the future, especially with its "spotty service record."

TPG Capital has a history of working with airlines. Since the main purpose for private-equity companies is to make a profit on their investments, it is only logical to think that Northwest could one day own Midwest outright. It's also possible that TPG could sell the company to AirTran years down the tarmac. Either way, the cookies are safe, for now.