That doesn't seem logical, the backing paper is dark and opaque, how could light pass through it and only pass through the numbers as if they were cutouts? They are ink, not cutouts. I have TMAX 100 and Portra 160 rolls from the same exact session with absolutely no issues, no light leaks, no watermarks. A light leak would at least show up with organic light shapes, which is not present in this problem roll anywhere. These are new TMAX400 rolls from B&H...this is not a light leak.
Edit: these folks at APUG were recently diagnosing this same exact issue, this is no light leak
(there was a url link here which no longer exists)
I mentioned light leak because of the apparent streak of light across the entire corner of the film, that looks like light leak to me, but what do I know?
I did also mention a possible chemical problem where the ink from the numbers could chemically develop a latent image on the film. It does appear from your link that there's a Kodak issue at hand, though I've bought new film from Kodak recently and so far haven't had an issue, I'll have to test a roll from the newest order now, either way be sure to load the camera in the shade and not expose the rolls to unnecessary light, seems the paper might be too thin, remember backing paper isn't light proof, just light resistant.
Good luck, It can be an ink and chemical exposure issue if the whole roll is the same.
If in fact the roll starts stronger at one end and gets weaker as the numbers go, then it's probably a backing paper light leak THROUGH the paper backing when rolled up issue, in which case, stay out of the light.
Seems like a possibly large issue based on the linked thread though, sorry to hear. Best of luck.
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