The proprietariness of gif has an expiry date. That expiry date has passed for those of us in the USA. It will be over in every country on June 20, 2004. See this timeline. Given the legal climate in Europe, I doubt that the European version was ever enforcible. (IANAL and all that.) Those two between them cover most of Perlmonks.

Therefore the issue of not using .gif for intellectual property reasons is lessening in importance, and all things considered, I would not worry about it too much. (FWIW I am in the USA, where it expired already.)