This was signed at the earliest in 1985 but it has Bruce's older, more formal signature more common in the 1970s. Anyone ever seen a BUSA era signature with that type of "S" in his last name? I have not.
For example here is a documented 1985 signature. Looks nothing like the one in Heritage's Auction. I think the forger was copying Bruce's earlier signature and Heritage didn't notice it. Hard to believe from a major auction house.