Half-Blood Prince Error “Old News,” Says Bloomsbury

British tabloid The Sun recently reported that there had been an error in Half-Blood Prince regarding the number of O.W.L.s Hermione receives compared to the number she sat in book five. Fans had originally spotted the error, but Bloomsbury told Leaky the error is at least a year old, spotted well before the latest rash of reports.
“This error was spotted as soon as HBP was published and it was corrected immediately,” said a spokesperson. “So this is very old news.”

The correction states that Hermione could only receive 10 O.W.L.s, not the 11 she is said to receive in book six.