It seems to be true.

Jigsaw puzzle companies tend to use the same cut patterns for multiple puzzles. This makes the pieces interchangeable. As a result, I sometimes find that I can combine portions from two or more puzzles to make a surreal picture that the publisher never imagined. I take great pleasure in “discovering” such bizarre images lying latent, sometimes for decades, within the pieces of ordinary mass-produced puzzles. As I shift the pieces back and forth, trying different combinations, I feel like an archaeologist unearthing a hidden artifact.