Chuck Greenberg has filed the paperwork and has been approved as a potential buyer for the Stars, according to a source. Greenberg, who helped a group led by Nolan Ryan purchase the Texas Rangers last August and is no longer with the organization, is now able to explore the club's financial records and determine if he wants to put in a bid. Vancouver businessman Tom Gaglardi is still in an exclusive negotiating window and could have a signed purchase agreement at some point soon.