The posting system between MLB and NPB has expired, so a new system will have to be put in place before Masahiro Tanaka can come to America. Joel Sherman reports that a new posting system will be agreed upon by November 1 and while radical changes were expected to be made, such as having the three top bids win the posting fee, that doesn't seem to be the case. Changes will be made, but still only one team will be awarded negotiating rights.
The posting system was initially created to give Japanese teams a reward for allowing their players to go to America. Players need to accumulate nine years of service time to gain free agency from the Nippon Professional Baseball league.
Tanaka will be able to post once an agreement is struck and the NPB season ends. The posting fee will likely coast around $50-60 million while his final contract could be in the six year, $60 million range.