Updated from 11:47 a.m. ESTIf someone is going to buy Bristol-Myers Squibb ( BMY), then Sanofi-Aventis ( SNY) would appear to be the most logical choice. The French drugmaker has the size and the ambition to make a deal, and these companies know each other well because Sanofi-Aventis licenses the U.S. marketing rights for several big products to Bristol-Myers. The most notable of those is the anticoagulant Plavix, the New York drugmaker's biggest product, but Sanofi-Aventis also licenses the blood pressure drugs Avapro and Avalide, fourth in sales for Bristol-Myers. In fact, Sanofi-Aventis probably knows more about its partner than anyone except the Securities and Exchange Commission, the U.S. Justice Department and patent attorneys. And therein lies the key to the report, from French financial newsletter La Lettre de l'Expansion, that the companies might announce a merger in the next few weeks. If the report is accurate, then Sanofi-Aventis is betting that Bristol-Myers' newer drugs and potential R&D stars will offset many concerns on Wall Street. Generic competition, past problems with U.S. regulators, uncertainty over a Plavix patent challenge and possible future actions by the DOJ have been dark clouds hanging over Bristol-Myers for some time. Representatives of both companies declined to comment. Shares of Bristol-Myers were up $1.44, or 5.5%, to $27.65, a 52-week high, on trading volume that was much heavier than normal. Sanofi-Aventis declined 69 cents, or 1.5%, to $44.65.