The 6th book called “Harry Potter and the Half-Blood Prince” was accidentally in circulation for enough time for 14 people in Canada to purchase it.
Of course by court order the 14 people that did the purchase kept their book but are not allowed to say anything about it until the official world-wide release this Saturday.
In return I think the will get their books signed by the author.
They are now the keepers of the secret. Lucky themâ€¦