Anne Frank, image via Reuters.

In the United States, Anne Frank: The Diary of a Young Girl will go into the public domain in 2047, ninety-five years after it was first published in 1952. In most of Europe, though, it might be out of copyright as early as January 1, 2016. Or 2051. Or maybe later.

According to Doreen Carvajal’s report in the New York Times, that depends on whom you consider to be “the author” of the book.

In his prologue to the first edition, Anne Frank’s father, Otto Frank, made it clear that the diary was written by Anne—a fact that isn’t in dispute. However, the foundation Mr. Frank established in Anne’s memory, the Anne Frank Fonds, recently released an announcement claiming that his editorial involvement in the book’s publication—the selection, editing, and arrangement of entries—constitutes a “new work.” Which effectively makes Mr. Frank a “co-author” and extends the copyright to seventy years after his death in 1980. It could be longer if the same claim can be made of Mirjam Pressler, who is still alive, and who revised, edited, and contributed additional material to the “definitive edition” of the diary, which was published in 1991.

The consequences of such an amendment to the byline of the diary could be steep for Anne Frank Fonds—as intellectual property attorney Agnès Tricoire told the New York Times: “If you follow their arguments, it means that they have lied for years about the fact that [the Diary] was only written by Anne Frank.”