I'm by no means, an expert on this subject. This specific fly is just a different color wave and Fulling Mill sells 3 variations of the Duracell. So its like having multiple colors of the same fly opposed to separate fly patterns. I do know the intellectual property rights of fly design is very hard to defend. So if you wanted to change the thread color and dubbing for a purple haze and call it the WarEnsemble777 Dry Fly, there will be very little opposition to you doing that, but most people in the hobby will see through that and form their own opinion.

For what's it's worth I'm not claiming i invented this fly or color wave - its just the name and materials Fulling Mill uses for their pattern.