Image source: Getty Images.Whether through cash donations or through providing their products and services free of charge to people and nonprofits in need, corporations across America are making billions of dollars' worth of charitable donations each year. Here's the list of the nation's 12 most charitable companies, according to The Chronicle of Philanthropy's mid-2016 report (registration required), along with some of the causes these companies are giving to. Image source: ExxonMobil.