(Having had to fight a legal case which involved, amongst other things, a publisher filing fraudulent copyright notices some years after the publication of the work I wrote for him, claiming on those notices to have written what I wrote, and claiming that these were valid copyright notices and I had lost my copyright because I hadn't found out about them within the the three years of the statute of limitations of copyright, I may be slightly more sensitive to the issue of losing one's copyright than most. Then again, I won the case.)