Teams that are member of the MPCC technically can't sign Fränk Schleck, which means they can't sign Andy.
Out of the current Tour peloton, that leaves according to Tageblatt Sky, BMC, Euskaltel, Movistar, Cannondale and OPQS. (Is Saxo part of the MPCC? Or did they just assume Schlecks and Riis would not work out anymore?)
If we take out the obvious like Sky, BMC, Euskaltel and Movistar, it only leaves Cannondale and OPQS.
Lefevere is quoted in this article as saying, "if I did sign a rider like that (GC rider), it would be someone younger than the Schlecks".
Which only leaves Cannondale. Fränk reunited with his old friend Basso? (No clinic pun intended) It's a possibility. But I think much less probable than the Schlecks staying with Trek.
Most teams can't sign them either because of moral or financial reasons. Others simply don't want to or don't have the need. They are facing very little options here.
http://www.tageblatt.lu/sport/dossier/tdf2013/story/Alles-deutet-auf-Verbleib-bei-Trek-hin-31493195