Eric O'Grady

Eric O'Grady was a former employee of Pym Tech. During an event that founders Hank Pym and Janet van Dyne were holding at the Pym Tech Building, fellow employee Elihas Starr, accidentally caused a chemical explosion which killed Grady and a couple other employee's. Starr, being fired and angry at Pym, took Grady's remaining DNA and created Black Ant, an exact clone of Grady to get revenge on Pym.