What Trademark Law Protects and the Limits of That Protection

The Color of a UPS Truck Is Legally Protected

UPS holds a registered trademark on the specific shade of brown — Pantone 462 C — used on its delivery trucks, uniforms, and branding. Tiffany & Co. has trademark protection for its robin's-egg blue (Pantone 1837). Owens-Corning has protected the color pink for fiberglass insulation since 1985. The scope of trademark law extends well beyond obvious brand identifiers like company names and logos to cover any distinctive sign capable of distinguishing a company's goods or services from those of competitors — including, under the right circumstances, colors, sounds, scents, and building designs. Understanding what trademark law actually protects — and what it cannot — requires understanding the law's fundamental purpose: preventing consumer confusion, not creating monopolies on commercial symbols.

What Can Be Trademarked

The Distinctiveness Spectrum

Trademark law organizes marks along a spectrum of inherent distinctiveness that determines how easily they qualify for protection:

• Fanciful marks are invented words with no dictionary meaning — Kodak, Xerox, Häagen-Dazs. They receive the strongest protection because they have no meaning other than as brand identifiers.
• Arbitrary marks are real words applied to unrelated products — Apple for computers, Amazon for a retail store. Also strongly protected.
• Suggestive marks hint at a product quality without directly describing it — Netflix (net + flix, suggesting internet movies), Coppertone (suggesting sun protection). Protected without proof of acquired distinctiveness.
• Descriptive marks directly describe a product characteristic — Cold and Creamy for ice cream, 5-Minute for epoxy glue. Not inherently protectable but can acquire trademark status through extensive use and consumer recognition (acquired distinctiveness or secondary meaning).
• Generic terms are the common name for a product — aspirin, escalator, thermos, trampoline — and can never be protected. When a trademark becomes so associated with a product category that consumers use it as the category name (genericide), it can lose trademark protection.

Likelihood of Confusion: The Core Infringement Test

Trademark infringement requires proving that an accused mark is likely to cause consumer confusion as to the source, sponsorship, or affiliation of goods or services. Courts apply a multi-factor test — in the Second Circuit, the Polaroid factors; in the Ninth Circuit, the Sleekcraft factors — that weighs considerations including:

The strength of the senior mark (famous marks like APPLE receive broader protection than weak descriptive marks). The similarity of the marks in sight, sound, and meaning. The relatedness of the goods or services. The sophistication of the consumer (purchasers of expensive professional equipment are assumed to exercise more care than buyers of inexpensive consumer goods). Evidence of actual confusion, if any exists. The channels of trade and advertising.

No single factor is determinative, and courts weigh the totality of circumstances. A defendant whose mark is similar but whose goods are in a completely different market may avoid infringement; a defendant whose mark is nearly identical in the same market almost certainly will not.

The Functionality Doctrine: What Trademark Cannot Protect

Trademark law explicitly cannot protect functional product features. If a design feature makes a product work better, cheaper, or easier to manufacture, it cannot be monopolized through trademark — that is the province of utility patents, which expire. Allowing trademark in functional features would create perpetual monopolies over useful inventions after their patents expired.

The Supreme Court's TrafFix Devices v. Marketing Displays (2001) decision clarified that a feature is functional if it is essential to the use or purpose of the product or affects its cost or quality, and that prior patent protection for the feature is strong evidence of functionality. The Louboutin red-soled shoe case produced a notable application of the doctrine: the Second Circuit found in 2012 that the red sole could be trademarked when it contrasts with the rest of the shoe, but not when the entire shoe is red, because restricting all red-soled shoes from competitors would unduly restrict competition in the shoe market.

Geographic Scope and International Protection

Famous Marks and Dilution

Marks that achieve fame — a higher legal threshold than ordinary trademark recognition — gain additional protection against dilution even without consumer confusion. Trademark dilution can be by blurring (weakening the distinctive association of a famous mark through unauthorized use by others) or tarnishment (associating a famous mark with objectionable or disparaging content).

The Federal Trademark Dilution Act (1995) and Trademark Dilution Revision Act (2006) created a federal dilution cause of action for famous marks. Courts have found that marks including KODAK, TIFFANY, MCDONALD'S, and APPLE qualify as famous for dilution purposes. Dilution claims allow companies like Louis Vuitton to successfully sue sellers of LV-monogrammed goods that consumers would not confuse with authentic products but that, the company argues, blur the distinctiveness of its marks through widespread imitation.

This article is for informational purposes only and does not constitute legal advice.