Wall Street has seen its share of strange bedfellows, but a recent alliance of investors that took on Exxon Mobil was unprecedented.Last week, an activist investor successfully waged a battle to install three directors on the board of Exxon with the goal of pushing the energy giant to reduce its carbon footprint. The investor, a hedge fund called Engine No. 1, was virtually unknown before the fight.The tiny firm wouldn’t have had a chance were it not for an unusual twist: the support of some of Exxon’s biggest institutional investors. BlackRock, Vanguard and State Street voted against …
