All of the cloth items I make, or intend to make, potentially for sale to the public are original designs or variations of existing items based on what I
think would be the best way to make that item both in its construction and appearance.
I consider each of the final products to be my intellectual property but not something that could be patented ( unless there was something drastically different about it)
The only practical way I can see to show that I have not simply used an existing pattern or item made from a pattern ( in other words someone elses work ) is to make up a set of working drawings and construction directions and have them notarized to show the date they where completed. I suppose I could also swear out a statement indicating that the item in question was my original idea as well.
I also realize that neither of these efforts would probably hold up in court because they still don't show that I didn't actually just steal the idea from someone else but, I think if you carefully document your design process and show a history of consistently doing so along with a demonstrated ability to actually make your own designs "out of thin air", that a person might stand a chance in court.
I don't imagine that my work is so "cutting edge" that I will be chased into court every time I try to sell something but, I do suspect that bigger companies may try to protect their market share by actively discouraging competition in this way.
As far as making stuff for sale to the public from someone elses copyright protected pattern goes I'm not sure I see the validity of the copyright protection extending to this level.
After all it was pointed out that pattern companies are in the business to sell physical patterns of an idea for a garment or cloth item.
If I buy a companies pattern and reproduce the unaltered pattern (photo copy, etc...) and sell it, then I can see the copyright infringement.
But, if I buy the same pattern and alter it to fit myself or any one else then I don't see how the pattern company has any claim to what I do with the end result.
If I use someone elses copyrighted pattern to mass produce something and I don't get a license from the copyright owner (in other words "cut them in on it") then I can see a clear problem although, I do wonder how that would be presented in court, after all I think it would fall upon the claimant to prove that the idea was originally theirs and not merely a copy of .......
In reality I am only making the physical result of following their pattern NOT making copies of the actual pattern and selling them.
After all is said and done, this is still America where one is "innocent until proven guilty" so the burden of proof lies on the prosecution and the claimant.
I think if a potential defendant has a history of going on line regularly to see what everyone else is making and how they are doing it then, you might have a problem.
If you can demonstrate your ability to create original works and produce them by your own skill then I would think you're all right.
If you follow patent infringement cases you will see this is the how things work during the trials.
Who can say that two competing companies didn't come up with the same idea at the same time. The one that wins the court battle is the one with the best process documentation and development history.
I'm not a lawyer and I don't play one on TV but, the above is only my considered opinion and some may consider it to be from some other planet but, it gets me through the day...