You cannot copy a pattern and then make changes to call it your own -it isn't the little details that are copyrighted, it is the creativity that is copyrighted. Taking someone else's experience, training, thinking, effort and more effort and using it to make a shortcut as though you had that training, experience and time invested is not only a copyright violation, it is not ethical. There is no iffy line, there is a very solid line drawn with a big black marker - if someone else created it, it belongs to them. Period.... You can freely copy it seventy years after their death.
Also, there is no difference between personal use and and any other use. Any copying without permission for any use at all is a copyright violation.
Knowing that, and knowing how much time and effort goes into making a rug, it is absolutely foolish to take any chances.
An example is a rug that was made by a superb hooker, a rug that was so well designed and made that it was selected for Celebrations - but, the central motif was of something that seemed like it belonged to all of our childhoods, much like a bicycle or a little red wagon, but that particular item was a copyrighted logo. When the superb hooker learned from Celebrations that she'd have to have a statement of permission from the logo copyright owner, she immediately sent off a letter to the company - and they said NO. A wonderful big beautiful rug, and she was told she could not dispaly it anywhere.
You never know ahead of time what you might want to do with a rug in the future - it just isn't worth the gamble to denigrate your own ability by taking something that belongs to someone else.
If you don't hold the copyright, you don't have the right to copyPhyllis Lindblade