guessing publisher from ISBN prefix

ISBN number is structured and contains four parts of information: Group or country identifier, Publisher identifier, Title identifier and check digits. Because ISBN are allocated by blocks to publishers, all ISBNs in same block should have same publisher information. So it's possible to guess ISBN's publisher information from its structure, however this will only work well when there is a big database of ISBN-prefix and corresponding publisher name. Incidentally, there are over 19 million ISBNs in xISBN database, from this database, we can actually create a rather comprehensive ISBN-prefix database. Inspired by Publisher Name Server project in OCLC Research, in last data release we count 551,528 ISBN publisher-prefixes, and it is not very far away from ISBN agency's directory ( 880,000 prefixes) . From our ISBN prefix table, we add "guessing" service for xISBN, which tries to guess publisher information of any ISBN, even they are not covered by Worldcat, such as following:

http://xisbn.worldcat.org/webservices/xid/isbn/7806281622.js?method=hyphen

returns

{"stat":"ok",
 "list":[{
	"isbn":["7-80628-162-2"],
	"area":"China, People's Republic",
	"publisher":"San Qin chu ban she",
	"city":"Xi'an Shi"}]}

It will be interesting to see how this information can be used. On the other side, the "guessing" service is still approximate, we don't know all ISBN prefixes, and sometimes one ISBN prefix doesn't neatly identify one publisher, so use with caution.