In a misguided attempt to ensure bibliophiles have bona-fide author autographs, California lawmakers have just imposed a huge hassle on booksellers.

Starting next month, if a bookstore sells an autographed book for $5 or more, it must guarantee the authenticity of the author’s signature. To do so, booksellers must both identify the book’s previous owner and offer a certificate of authenticity.

Booksellers that don’t meet this exacting standard face massive fines—they’re “liable for a civil penalty equal to 10 times actual damages, plus court costs and other charges,” the New York Times reports.

One antique bookseller in Eureka, Califronia, broke down the likely unintended consequences in a blog:

Consider bookstores that do a lot of author events. Let’s imagine that Neil Gaiman does one of his typical massive book signings in February for his forthcoming book, Norse Mythology. Say 1000 people show up and buy books at $25.95. The bookstore either has to issue 1000 COA, or risk being sued for $25.95 x 1000 x 10, plus attorney’s fees. Call it $300,000.

Is it any wonder that many of California’s best bookstores are very worried that this law will make it much harder to hold book signings and other author events. The legislature and the governor apparently had a similar response, because the law was passed with almost no discussion.

There are also privacy concerns, as the New York Times notes:

“If you visit my bookstore to trade in that copy of ‘Hillbilly Elegy’ you picked up at a book signing, I’ll need to take down your name and address and then provide it to whoever happens to buy the book from me,” said Scott Brown, who runs Eureka Books in Eureka.

… “I can understand why booksellers are concerned,” said Michael Risher, a lawyer attorney with the A.C.L.U. of Northern California. “The law is an invasion into privacy and should be amended.”

This is a terrific example of how a big government with good intentions often hurts the very people it hopes to protect.