Well, I remember that being part of the contention. Sony said, "we've patented it". Everyone else said, "how can you have patented it, when you won't tell anyone what it is!?". Or something along those lines.
I think at the time what I found ridiculous was that you were prohibited from "having" the number, but of course nobody could say what number it was you weren't allowed to have... seemed like something that belonged in Dr. Strangelove.
