The note — plus another heart-shaped message addressed to someone called “Joan” — was hidden in a piece of cardboard at the center of a new pair of Argyle socks, Seidemann wrote. It’s not clear who wrote the note or slipped it into the socks. The filing didn’t say, and prosecutors later declined to elaborate.

Prosecutors revealed heart-shaped notes were hidden among socks later given to Luigi Mangione, who is charged in the killing of CEO Brian Thompson.