Thunderbolt - 1992

I think Pete Cannon, Thunderbolt, holds the distinction of being the only comics character that was bought by DC but now is no longer owned by DC, unlike his fellow Charlton alumni.

...on second thought, strike that. I think DC doesn't own the old Fawcett characters Bulletman and Bulletgirl, either. In any case, that was the first thing I thought of when I saw this ad--that DC couldn't revive this, even if they wanted to!