Mass. Gen. Laws ch. 266 § 139A
Whoever removes, defaces, alters, changes, destroys, obliterates or mutilates or causes to be removed or destroyed or in any way defaced, altered, changed, obliterated or mutilated, the identifying number or numbers of any machine or any electrical or mechanical device, with intent thereby to conceal its identity, to defraud the manufacturer, seller, or purchaser, to hinder competition in the areas of sales and servicing, or to prevent the detection of a crime shall be punished by a fine of not more than five hundred dollars or by imprisonment in a jail or house of correction for not more than one year or by both such fine and imprisonment. Possession of any machine or electrical or mechanical device the identifying number or numbers of which have been so removed, defaced, altered, changed, destroyed, obliterated or mutilated shall be prima facie evidence of a violation of the foregoing provision.
Whoever sells or otherwise disposes of or attempts to sell or otherwise dispose of a machine or an electrical or a mechanical device, knowing or having reason to believe that the identifying number or numbers of the same have been so removed, defaced, altered, changed, destroyed, obliterated or mutilated, shall be punished by a fine of not more than five hundred dollars or by imprisonment for not more than one year in a jail or house of correction or by both such fine and imprisonment.
Mass. Gen. Laws ch. 266, § 139A