Source: Mike Florio, NBC Sports Pro Football Talk 
We’ve since acquired some more information about the little-known and largely misunderstood device for giving teams extra draft picks to replace the veterans who have left for free agency, specifically as the process applies to Vikings defensive end Jared Allen.
Despite widespread reports and speculation that the Vikings would get a third-round compensatory pick in 2015 if Allen leaves as a free agent in 2014, a source with knowledge of the formula tells PFT that the Vikings would be limited to a fifth-round compensatory pick for Allen.
Vikings are certainly open to fielding offers today for Jared Allen. Have had a few talks w teams but nothing substantial yet
— Jay Glazer (@JayGlazer) October 29, 2013