IT IS ILLEGAL TO COPY OR RESELL items with trademarks or copy rights
There are plenty of patterns out there being made and sold by people using their personal software.
There are plenty of patterns on-line that are torn from magazine pages.
Lots of official patterns being resold
Almost all patterns come with the warning that it is illegal to copy and resell.
I even purchased a legitimate pattern once that said that I was only allowed to stitch it one time. That was a little extreme to me -- it is my pattern and I will stitch it as many times as I choose. Started it but never finished.
I have taken patterns that I purchased to Kinko's and they have refused to make even one copy for my own personal use.
Disney has the right to take action against someone that makes patterns using their licensed characters and re-sell the.
The company owing the right to the pattern being sold has the right to take action against someone reselling their products.
I don't know how or why you can buy old patterns at used book stores.
I remember a case a few years back. McDonalds went after a young woman with a Scottish heritage who started her own business (don't remember what it was). She called her company by her first name and part of her last name Don't remember what it was -- let's call her Rosie for the sake of this example. So the company was called Rosie McDs. McDonald's when after her for trademark violation.
They chose to make an example of her. Don't know what happened.
Sharing copies of a pattern with someone could be compared to downloading music or "sharing" cable TV access.
Again, I am not telling you what you should do.
I will not recommend point anyone on this site to a non-official site for patterns.