The lives of antique booksellers in California are about to get a little harder if a state law that’s just been passed takes effect next year.

The law in question goes by the name “AB-1570 Collectibles: sale of autographed memorabilia,” and governs the sales of any autographed items. The law supersedes existing California law, which had previously only been directed at sports memorabilia. The law requires that any autographed item sold for more than $5 must include a certificate of authenticity including information about the dealer, where and how the item was signed, and the name and address of any third party from whom it was purchased. The law was undoubtedly aimed at shutting down forgery mills, but it was written so broadly that it will make things a lot harder for anyone dealing in autographed goods.

You don’t have to think about this law for very long before you realize how problematic it would be for antique and second-hand booksellers, some of whom carry hundreds or thousands of autographed copies of books. Given that few such books would sell for less than $5, this means that these booksellers must either create individual certificates of authenticity for each book, or else discard thousands of dollars in inventory that is no longer salable. Even if they were to create such certificates, in the case of a third party purchase the certificates would have to include the personal information of whoever sold it to them–a clear violation of privacy.

It would also apply to any art gallery that sold original works–and the ramifications for San Diego Comic Con and other conventions that have “artist’s alleys” where artists can set up booths to sell (and autograph) their own artwork might also be considerable–to say nothing of authors who set up to do the same thing for their books. What if everyone who sold an autographed book or sketch had to make out a certificate of authenticity when they sold it? (The law says that “the person who signed the memorabilia” isn’t considered a “dealer,” but if they’re also the one who sells the work in question, they should still be on the hook for it.) Likewise, it will also affect out-of-state dealers who want to sell to California residents, or who come to those conventions to display their art.

It’s hard to believe this law could have been passed without any consultation or notification of the people most likely to be affected by it, but it did, and it’s set to take effect on the first of the year. The owners of Eureka Books and Book Passage are writing their representatives pointing out the problems with the law. It remains to be seen whether their protests will have any effect.

Of course, this is an area where ebooks have little cause for concern, given that “autographed” ebooks aren’t currently a thing (despite the efforts of companies like Autography, Barnes & Noble, and Keeper Kase to make it possible) and even if they were, you couldn’t resell them after you got them signed. But people still like reading paper books, and they also like having them signed as tangible proof they met the author. It sounds like this ill-considered law will make that a whole lot more complicated for everybody.