Originally Posted by
vickig626
my quilt instructor told me that if you take a pattern you like and want to make your own spin on it, you need to change it by at least 30% from the original...then it becomes your own. Sometimes when I find a purse or bag pattern I like, the instructions can be horrible. I showed her how I had to rewrite the instructions (for myself) then end up making a lot of changes to the pattern, she said it's now my pattern because of the amount of changes made. The bag looks similar but quite a bit different from the original. Not sure if this helps or not but thought I'd pass this along.
Your quilt instructor is wrong, just plain wrong. If the derivative work (your 'changed' version) can be identified as being derived from the original work at all, it is a copyright violation. There is no set amount of change involved.
Originally Posted by rush88888
copyright can expire, but i am not sure how long that would be for any given material.
As a general rule, for work created after January 1, 1978, it is the life of the copyright holder plus 70 years.
http://copyright.cornell.edu/resources/publicdomain.cfm