Yesterday I made four exposures of two objects with a Linhof Technika. I used two different film holders, and I got one plate ok and the other with a light leak, on both holders, as is shown here:

film holder 1 a.jpg holder 1a film holder 1 b.jpg holder 1b film holder 2 a.jpg holder 2a film holder 2 b.jpg holder 2b

Besides the probable explanation of not fit the holder properly, twice, there is any other reason you can figure out?, should I see if there is something wrong in the holders? or the camera?, where do I have to search.