October 7, 2026
Many foreign brand owners reach the United States through the Madrid Protocol, designating the U.S. in an international registration administered by WIPO. At the USPTO, this is treated as an application under Section 66(a) of the Trademark Act. It is convenient, but it carries rules that a direct U.S. filing does not. Here are the issues that come up most often.
A 66(a) Filing Is Examined Like a U.S. Application
Under 37 CFR § 7.25, most of the USPTO's Part 2 trademark rules apply to an extension of protection, with listed exceptions. The Office refers to the request as "an application under section 66(a)." In practice, a Madrid designation faces the same substantive examination as any U.S. application: likelihood of confusion, descriptiveness, identification of goods and services, and the other usual requirements. Any refusal must be answered through U.S. counsel when the holder is foreign-domiciled (37 CFR § 2.11).
Identification of Goods and Services
An international registration's list of goods and services is often drafted to satisfy another office's practice. The USPTO frequently requires more specific wording. Responding to these requirements is one of the most common tasks in a 66(a) file, and the response needs care so that coverage stays within what the international registration supports.
You Cannot Change the Basis
Under 37 CFR § 2.34(b), "a basis under section 66(a) of the Act may not be combined with another basis." Under § 2.35(a), a 66(a) applicant "may not add, substitute or delete a basis," except through transformation (discussed below). A direct U.S. applicant can move between use, intent-to-use, and Section 44 bases. A Madrid applicant cannot.
No Supplemental Register
Under 37 CFR § 2.47(c), "an application under section 66(a) of the Act is not eligible for registration on the Supplemental Register." That matters when a mark is refused as merely descriptive. A direct U.S. applicant might amend to the Supplemental Register, but a 66(a) applicant has to overcome the refusal on the Principal Register, for example by argument or a claim of acquired distinctiveness, or accept the refusal.
Use Is Not Required to Register, but Intent Is
A 66(a) request must contain a signed declaration meeting 37 CFR § 2.33(a) and (e) (§ 2.34(a)(5)). That declaration covers, among other things, a bona fide intention to use the mark in commerce. No specimen is required to register. Use becomes essential later, because the registration must be maintained by showing use in U.S. commerce (see our maintenance article).
Dependency on the International Registration
A U.S. extension of protection is tied to the international registration. Under 37 CFR § 7.30, when WIPO's International Bureau notifies the USPTO that the international registration has been cancelled or has expired, in whole or in part, the USPTO cancels the corresponding U.S. extension to the same extent.
Transformation is the safety valve. Under 37 CFR § 7.31, if the International Bureau cancels the international registration under Article 6(4) of the Protocol, the holder may, within three months of the cancellation date, request to transform the affected goods or services into a U.S. application under Section 1 or 44. If the request is complete, the new application keeps the same filing date and priority. Calendaring that three-month window is critical.
Direct Filing or Madrid?
Neither route is always better. Madrid offers centralized administration. A direct U.S. or Section 44 filing offers more flexibility on basis, access to the Supplemental Register, and independence from the home registration. Compare our article on Section 44(e) and 44(d). For firms managing Madrid portfolios that need a U.S. associate, see our page for foreign law firms and associate counsel.
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Start Your Trademark Intake For Foreign Law FirmsThis article is general information, not legal advice, and reading it does not create an attorney-client relationship. Every situation depends on its own facts, and no particular outcome can be guaranteed. Laws and government fees change; confirm current requirements before acting.
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