File this under “things I always thought were true, but realized couldn’t be true, that actually are true.” Sort of.
From the Wikipedia entry for Armand Hammer:
In the 1980s Hammer owned a considerable amount of stock in Church & Dwight, the company that manufactures Arm & Hammer products; he also served on its board of directors. However, the Arm & Hammer company’s brand name did not originate with Armand Hammer. It was in use some 31 years before Hammer was born. He was spurred to buy shares in the company as a result of often being asked about the brand being so close to his name.