[Silhouette]

Even then I'm not convinced, without talking to a lawyer, that it would be safe to recreate in a patent-encumbered format.

Regardless of how well patents in general might or might not serve their original purpose, I tend to think that patents that are essentially just locking up data formats do not encourage progress in the way that they are supposed to. I think the US was onto something when it came to copyright and typeface designs, and a similar principle ought to apply to data formats.

[michaelfeathers]

I think this is a non-issue for the bulk of any business that does this. An Microsoft or Apple is going to sue a business that upgrades documents in old formats to their newer formats? Maybe, but I'd be surprised. If anything there'd probably be licensing.