First edition, first impression, first state, with the requisite points: the number series on the copyright page from 10 down to 1, "Joanne Rowling" as the copyright holder, and the dropped line of text on page 7. In the second state, the dropped text is corrected and the copyright is attributed to "J. K. Rowling". Copies in fine condition are increasingly uncommon.
"The book trade has generally thought that there were 2,500 copies of the first issue" (Errington). It was the last title in the series before first print runs hit unprecedented quantities.
Octavo. Original illustrated boards lettered in various colours. With dust jacket.
A fine copy in fine, unclipped dust jacket.
Errington A7(a).