Both trademark infringement and false advertising are understandable as species of unfair competition, related in that both operate to protect consumers and competitors against distortion in the market caused by misleading information. But they have differing subject matter and often different tests for liability for the same type of claim. In particular, advertisers often want to make comparative claims identifying a particular competitor, whether by name or by some other recognizable characteristic. If these claims are false, no separate principle of trademark law is required to conclude that they should be banned, even if they are neither confusing in the trademark sense nor disparaging. For example, if ads falsely claim the advertiser’s product is as good on some specific measure as the trademark owner’s product while clearly indicating the separate source, false advertising law prohibits the claim. However, if claims such as “cheaper than Brand X, but just as effective” are not false or misleading, then general advertising law allows them – unless trademark law has some separate force in controlling advertising claims that aren’t about the source or sponsorship of the advertiser’s product.