The parent body of the Farmington meteorite experienced sufficient heating, probably from shock accompanying a major collision occurring at 520 × 106years ago, to erase the record of any magnetization acquired prior to that event. Therefore, the observed magnetization in the Farmington meteorite must have been acquired after the collision. Shock‐produced magnetization is unlikely because of the finite cooling time indicated by the burial depth of ≥ several meters. The possibility of shock or irradiation‐produced magnetizations should be studied experimentally, even though neither appears likely to have produced the magnetic field which produced the magnetization in the parent body of the Farmington met