Kingsfield · Research · Intellectual Property

What must a registered trademark owner show to hold an infringer liable under the Lanham Act?

Published 2026-06-23 · U.S. federal law

Section 1114 lets the owner of a registered mark sue anyone who uses a reproduction or colorable imitation in commerce where the use is likely to cause confusion.

The answer

The registrant's cause of action

15 U.S.C. § 1114 imposes civil liability on any person who, without the registrant's consent, uses in commerce a reproduction, counterfeit, copy, or colorable imitation of a registered mark in connection with the sale or advertising of goods or services, where such use is likely to cause confusion, mistake, or deception. The right of action under this section runs to the registrant of the mark.

Registration is the predicate

Section 1114 protects marks that are registered on the principal register. An owner of an unregistered mark must look to a different provision of the Lanham Act for a federal remedy.

The judged input

What the AI drafted

Submitted to the judge

This is an excerpt from a draft trademark clearance memo — the kind of work product a lawyer generates with a legal-AI drafting tool, then has to stand behind. Kingsfield does not write it; it rules on the citations the model put in it. This draft cites two authorities; one of them is wrong.

AI draft excerpt — trademark clearance memo

We advise the Company that adopting the proposed logo carries meaningful infringement exposure to the senior registrant. Under 15 U.S.C. § 1114, the owner of a registered mark may hold liable any person who, without consent, uses in commerce a colorable imitation of the registered mark in connection with the sale of goods where the use is likely to cause confusion. Because the proposed logo is a near-identical imitation of a registered mark used on competing goods, the likelihood-of-confusion standard is readily met. The cause of action for infringement of a registered mark arises under 15 U.S.C. § 1125.

The judge ruled on every citation as the draft used it — it accepted 15 U.S.C. § 1114 and rejected 15 U.S.C. § 1125. Here is why.

The verdict

How Kingsfield ruled

Ruled 2026-06-23

Each citation in the draft above was submitted to the Kingsfield judge and ruled against the primary-law corpus — Accept, Reject, or Inconclusive, per citation. These are live verdicts, not editorial. Each card shows the claim the draft made and the verbatim authority the verdict was rendered against.

Accept15 U.S.C. § 1114

The draft claimed: Any person who, without consent of the registrant, uses in commerce a reproduction, counterfeit, copy, or colorable imitation of a registered mark in connection with the sale or advertising of goods or services, where such use is likely to cause confusion, mistake, or deception, is liable in a civil action by the registrant.

“§ 1114 Any person who shall, without the consent of the registrant—”

Cite found; proposition supported by the cited text.

Reject15 U.S.C. § 1125

The draft claimed: Section 1125 supplies the cause of action for infringement of a federally registered trademark, holding liable those who use a colorable imitation of a registered mark in commerce.

Cite found, but the cited text does not support the claim. 15 U.S.C. 1125 addresses false designation of origin and unfair competition (protecting unregistered marks and trade dress); the infringement claim for a registered mark is under 15 U.S.C. 1114. Regenerate with the correct authority.

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Kingsfield rules on every citation, quote, and proposition your AI produces, against the primary law we cover. Accept, Reject, or Inconclusive, per citation, with a signed Audit Capsule.

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This page is legal information, not legal advice, and does not create an attorney-client relationship. The draft shown is an illustration of a typical AI answer; verdicts reflect the cited authority in the Kingsfield corpus as of the ruling date shown above.