The number of e-books available for digital lending on Amazon’s Kindle through public libraries around the country has declined noticeably in recent days — from more than 27,000 to less than 23,000 titles through the Seattle Public Library, for example.

The reason: Penguin Group USA has decided, for now, to stop making new e-books available to libraries in digital form, and suspended all public library lending of its books for Amazon Kindle, reports Library Journal’s Digital Shift blog.

“We have always placed a high value on the role that libraries can play in connecting our authors with our readers,” a Penguin Group spokesperson said in a statement to the site. “However, due to new concerns about the security of our digital editions, we find it necessary to delay the availability of our new titles in the digital format while we resolve these concerns with our business partners.”

The publisher didn’t detail those security concerns.

Overdrive, which powers the service, reports on its site that Penguin sent a notice last week saying that it was reviewing the terms for library lending of its e-books, and “OverDrive was instructed to suspend availability of new Penguin eBook titles from our library catalog and disable ‘Get for Kindle’  functionality for all Penguin eBooks.”

Amazon launched the public library lending program in September.

Separately, the company this month announced a Kindle Owners’ Lending Library, allowing Amazon Prime subscribers to check out a book per month from a more limited catalog, without the participation of Penguin or other major U.S. book publishers.

Like what you're reading? Subscribe to GeekWire's free newsletters to catch every headline

Job Listings on GeekWork

Find more jobs on GeekWork. Employers, post a job here.