The draft was four rounds and all 19 MLS clubs participated .
The 2012 MLS Supplemental Draft was a secondary draft that was held by Major League Soccer via conference call on January 17 , 2012 .
The draft was four rounds and all 19 Major League Soccer clubs participated .
The 2012 MLS Supplemental Draft was a secondary draft that was held by Major League Soccer via conference call on January 17 , 2012 .