This is an attempt at a port of the Perl CPAN module Geo::StreetAddress::US to C#. It's a regex-based street address and street intersection parser for the United States.
The original Perl version was written and is copyrighted by Schuyler D. Erle <[email protected]> and is accessible at CPAN.
It says that "this library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.4 or, at your option, any later version of Perl 5 you may have available.".
According to the Perl licensing page, that seems to mean you have a choice between GPL V1 (or at your option, a later version) or the Artistic License.