Beginning with the first linear collider, SLC at SLAC, it was quickly discovered that high energy muons that are produced in halo collimators in the beam delivery system can cause a significant background in the experiment detector. Following publication of the ILC Technical Design Report, May 2013 [1] a simulation of this background has been made using simulation codes MUCARLO and GEANT4. It became clear that to mitigate this background, various magnetic devices were going to be needed.