The closest the government has come to naming a banned book was when it took action against some "problematic maps" that were banned back in 2011. The only other time that comes to mind was in 2014, when Reuters reported that books by eight prestigious Chinese authors were banned — but Xinhua refuted the story quickly and claimed that the report was false.
Even though there's no official list, reports have stated that at least one other bookstore's staffers have been told to pull "politically sensitive" books off the shelves, while some stores hide the books unless customers ask for them specifically.
Basically, everybody is confused over how to determine what kinds of books are "banned" books, including outspoken and influential Hong Kong writer and TV culture critic Leung Man-tao. "Does China have any regulation or law defining 'banned' book? The answer is no," he wrote in a recent column. If publications with official authorization are legal books, then those without the government's sign-off qualify as "illegal" publications, he explained.