Revision history for Perl module Business::ISIN. 0.20 Wed Feb 13 00:00:22 UTC 2001 - Added pseudo country codes XA, XB, XC, XD and XS. - Made error messages more informative. Thanks to Tim Ayers for the suggestion. 0.12 Tue Oct 9 19:17:35 BST 2001 - Made set() method return the ISIN object, rather than the ISIN as a string, to allow $isin->set("GB0004005475")->is_valid. (Note that stringification means that print $isin->set("GB0004005475") still works). 0.11 Thu Oct 4 21:22:51 BST 2001 - Fixed algorithm bug and checked against thousands of ISINs. Thanks to Peter Dintelmann for providing useful feedback and test data. - Added PS country code (Palestine). 0.10 Sat Sep 29 06:42:39 UTC 2001 - Changed algorithm to cope with ISINs containing letters, such as "US459056DG99". - Checked algorithm against draft copy of update of ISO 6166. 0.01 Sat Mar 10 15:17:41 UTC 2001 - Original version.