A complete discussion of copyright law is beyond our purpose here at “Tip of the Day,” but suffice it to say that a genealogical fact cannot be copyrighted. Your cousin in Arizona cannot copyright the fact that “John Smith was born in Maryland in 1783.”
What he can copyright is a report he compiled showing why that year of birth is correct. The report he would be within his rights to lay copyright claim to.
Of course, if he spent years uncovering a fact and you use that fact in a compilation, it might be nice to give him credit for “finding” that fact. If you don’t, he might not share anything with you again!
Several years ago, I sent transcriptions of documents to a distant relative. She posted them to US GenWeb archives. Her submission contains a footer saying the transcriptions are copyrighted by the submitter and cannot be used, transmitted, etc. by anyone else without permission.
She sent my transcriptions to the appropriate county GenWeb sites. These transcriptions are mine because they include my unintentional errors. I know she didn’t get the originals herself and retranscribe them making my exact same mistakes. I’m all for copyright protection, but don’t claim copyright to something someone else sends you.
I am all for sharing and do it regularly. But if you take what I share with you, claim it is all yours, and claim copyright to it, we are done sharing.