There are various sample lease forms floating around which don’t say they’re copyrighted. Does this mean you can use clauses or sentences from them ... or even use the entire lease form ... without worrying about copyright infringement?

I’ve heard of a law firm using one of these samples found freely on the Internet -- i.e., the Earthworks “Texas Sample Oil & Gas Lease” -- with the notation that it is copyrighted by their law firm, with all rights reserved. How can they do this if they didn’t write it?

And if you pay an attorney to do a lease for you, do you then own it ... in other words, can you use it, or parts of it, again for another lease ... or give it to others to use freely?