Magnusom-Moss Act

I have noted a lot of posts on FC about a car's warranty being voided for this or that and most recently about how Ferrari will void the warranty on an Enzo if you don't use their $75 per quart oil. However, the Magnusom-Moss Act prohibits a company from voiding a car's warranty because an aftermarket part or fluid is used UNLESS they can prove that aftermarket part or fluid caused the failure for which a warranty claim is being made. Just thought everyone would want to know.