In 2006, Congress changed federal trademark dilution law when it enacted the Trademark Dilution Revision Act (“TDRA”). This Article first outlines the history of the dilution doctrine in the United States so that the changes enacted through the TDRA may be understood contextually. The TDRA’s new provisions are then delineated and explained. The author argues that the TDRA narrows the scope of federal dilution protection. Although the TDRA lowered the burden of proof to a “likelihood of dilution” standard, the Act’s new definition of fame creates a high bar that will exclude many marks from qualifying for federal dilution protection. Finally, through a case study, the Article illustrates how the TDRA’s parody exemption will work as a defense against dilution by blurring and dilution by tarnishment claims.