Just Dinner? What's Up With Goldman & Morgan

Goldman Sach's Lloyd Blankfein and Morgan Stanley's John Mack

There’s an interesting Wall Street love story developing here, between John Mack CEO of Morgan Stanley and Lloyd Blankfein CEO of Goldman Sachs.

Traditionally, Goldman Sachs and Morgan Stanley have been bitter rivals, competing on deals and trashing each other to the press. But since the financial crisis began, Mack and Blankfein have become "best friends forever…"

CNBC has learned that the two have been dining together regularly, including this last Monday.

This is fueling speculation that the two firms, both under tremendous pressure as they change their business models from investment banks to commercial banks, are considering a merger of some sort.

Senior executives at both firms have said that this is not the case, these were not merger negotiations, but instead, informal strategy sessions. Both Mack and Blankfein know they face similar problems in remaking their firms and are sharing ideas.

Sources close to both firms tell me that this relationship became “increasingly intimate” just after the Lehman Brothers Holdings bankruptcy, and as shares of both Morgan and Goldman began to decline. That’s when they began dining together regularly.

The dinner took place at the Palm restaurant in Manhattan, and John Mack paid, sources say. As reported, Blankfein is not taking a bonus this year, so maybe that has something to do with it.

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