State law defines marriage as being between a man and a woman, but Hanes said the law discriminated against a class of people and was unconstitutional.
The validity of the licenses is in question, since they are not recognized by the state. The American Civil Liberties Union has sued the Corbett administration to legalize same-sex marriage in Pennsylvania, but the suit is not expected to be resolved for some time.
Additionally, the state has sued Hanes to stop his office from issuing the licenses. On Wednesday, Commonwealth Court agreed to an expedited review of the county's issuances of the licenses, but did not bar the county from issuing them in the meantime.
The court ordered the state to submit an argument by Monday. The county will then have until Aug. 19 to file an opposing argument.
Hanes said Friday's milestone came and went without much consternation. Despite the lawsuit and whatever hoopla has been stirred up by the licenses' issuance - appearances by reporters, for example, or pray-ins by peaceful protesters - issuing the licenses has become somewhat routine, he said.
"I think that we're at a point where all licenses are issued in the ordinary course of business," he said. "And I don't think it's caused a particular change in the office."
Contact Chris Palmer, 609-217-8305, firstname.lastname@example.org, or follow on Twitter, @cs_palmer