If shareholders crush the Glen-Xstrata merger tomorrow, the pain will be deep for the 10 investment banks that worked on the deal. BNP Paribas, which advised Glencore, would suffer the steepest fall in the global M&A adviser rankings, sliding from no. 14 to no. 23; BofA (BAC), which wasn’t on the deal, would benefit most, rising from no. 8 to no. 4.