U.S. stock futures wobbled ahead of the opening bell Monday morning following UBS's deal to buy smaller rival Credit Suisse, in a bid to avoid further market-shaking turmoil in global banking. “The market will need to digest the M&A from the weekend and then await the results of the FDIC auctions to see whether it agrees that contagion is contained,” the US Market Intelligence team at JPMorgan said in a note to clients.