The posting term for Koji Mitsui has come and gone without a single bidder for his services. I'm not too surprised by this; Mitsui is 35, coming off a bad year, and wanted a major league contract. Might as well sign Mark Hendrickson, who wouldn't cost a posting fee.
If Seibu wants to accomodate Mitsui at this point, they might choose to release Mitsui to allow him to pursue and MLB deal. He might have a better shot after some of the more proven guys sign. Nippon Ham was in a similiar situation with Yusaku Iriki a few years ago. The Fighters released Iriki after he failed to draw any bids during the posting process. Iriki went on to sign with the Mets, get busted for PED usage in the minor leagues, and eventually make his way back to Japan for one season before retiring.