Re: who owns the rights to fly patterns?
As to fly patterns, there's very few out there that have (or had) that designation. The Teeny Nymph comes to mind. Even with that, you're free to tie your own as long as 'it's not for commercial purposes.'
As for a picture/name of a fly, look at any on-line catalog and you'll (obviously) find hundreds. And many of these have 'step by step' description on the construction in tier books, magazines, etc.
As for the application something just rings in my mind that there's already something similar on line. Spotted it ages ago looking for something else.
All that aside, I wouldn't get worked up if you figure out how to pull this off.
"“Reputation is what the world thinks a man is; character is what he really is.”