Ok I love how all you idiots argue over what this sign is when none of of you are right. The sign was created by Ville Valo (lead singer of H.I.M) on his twentieth birthday. Described by Valo, the sign is a modern yin/yang, like good and evil together. Now, about Bam Margera. He loves the band and is good friends with Ville, so he got a few tattoos of heartagrams. Then he started using it as his "sign" and selling products with it on it. After he started making money off of it, he needed a licence on it. But, he didn't invent it. So, TOGETHER, Bam and Valo got a license/trademark on it. It belongs to both of them, so no need to argue anymore.
Ville Valo and Bam Margera have a joint license on the heartagram.