Patents

Deepsouth v. Laitram: The Loophole That Built §271(f)

The Supreme Court holds that exporting the unassembled parts of a patented machine for assembly abroad is not 'making' the invention—prompting Congress to rewrite the statute a decade later.

September 8, 2025
Disassembled industrial machine parts in shipping crates
Deepsouth held that shipping a patented machine in pieces for foreign assembly escaped infringement. Shutterstock
Educational content, not legal advice. This article explains general legal concepts. It does not create an attorney–client relationship. For your specific situation, consult a licensed attorney.

In Deepsouth Packing Co. v. Laitram Corp., No. 71-315 (U.S. May 30, 1972), the Supreme Court drew the territorial boundary of U.S. patent law in a way that would echo through every later extraterritoriality case—by leaving open a gap so conspicuous that Congress eventually legislated it shut. Argued April 11, 1972, and decided May 30, 1972, the case asked whether a domestic manufacturer infringes a U.S. combination patent by building all the parts of the patented machine in the United States, then shipping them abroad in pieces for one-hour assembly and use overseas. By a 5-4 vote, the Court said no. Justice White wrote for the majority, joined by Justices Douglas, Brennan, Stewart, and Marshall; Justice Blackmun dissented, joined by Chief Justice Burger and Justices Powell and Rehnquist.

At a glance

  • Case: Deepsouth Packing Co. v. Laitram Corp., No. 71-315
  • Court: Supreme Court of the United States
  • Argued / Decided: April 11, 1972 / May 30, 1972
  • Vote: 5-4 (reverse the Fifth Circuit)
  • Majority: White, J., joined by Douglas, Brennan, Stewart, and Marshall, JJ.
  • Dissent: Blackmun, J., joined by Burger, C.J., and Powell and Rehnquist, JJ.
  • Holding: A patented combination is “made” only when its parts are assembled into the operable whole; manufacturing the unassembled parts in the United States and exporting them for assembly abroad does not infringe a U.S. patent.

Laitram held patents on machines that deveined shrimp—a “slitter” that opened the shrimp and a “tumbler” that washed out the vein. Both were combination patents: the individual parts were unpatented, and the inventive contribution lay in the assembled apparatus. Deepsouth, enjoined from making and selling the assembled machines in the United States, devised a workaround. It would build all the components domestically, then ship them to foreign customers in three boxes—each holding only parts of the roughly 1¾-ton machine—where they could be bolted together in under an hour and used abroad. Deepsouth sought a declaration that this practice did not infringe. The Fifth Circuit held it did. The Supreme Court reversed.

”Makes” means the assembled combination

The statutory hook was 35 U.S.C. §271(a), which makes liable anyone who “makes, uses, or sells” a patented invention within the United States. The whole case turned on what it means to “make” a patented combination. The majority held that a combination patent protects only the operable assembly of its elements—the working whole—and that nothing is “made” until those elements are united. Because Deepsouth never assembled the machines in the United States (it shipped them in pieces precisely so that assembly would occur abroad), it never “made” the patented invention domestically. Manufacturing unpatented parts is not making the patented combination.

That conclusion rested on a foundational and old principle of patent law: a combination patent confers no monopoly over the constituent parts taken separately. The parts, standing alone, were free for anyone to make. Laitram’s exclusive right attached to the assembled machine, and that machine was assembled only outside the United States, beyond the reach of the U.S. patent grant.

The territorial premise

The majority framed its holding in unmistakably territorial terms. A U.S. patent, the Court said, has effect only within the United States and its territories; it confers no power to prevent others from “making, using, or selling” the invention abroad. Laitram’s patent could not reach the foreign assembly and foreign use of the machines, because patent rights stop at the national border. If Laitram wanted to control the shrimp-deveining market in foreign countries, the remedy lay in obtaining and enforcing patents under the laws of those countries—not in stretching the U.S. statute to cover conduct completed overseas.

The Court was candid that this produced an awkward result: a domestic manufacturer could lawfully capture foreign markets for a U.S.-patented machine simply by exporting it in kit form. But the majority insisted that expanding the patent monopoly to reach this conduct was a policy judgment for Congress, not a gap for the judiciary to fill by reinterpreting “makes.” The statute as written drew the line at domestic assembly, and the Court would not redraw it.

The dissent’s functional objection

Justice Blackmun’s dissent attacked the majority’s line as exalting form over substance. Deepsouth, he observed, made every part of the patented machine in the United States, assembled and tested the machines domestically to be sure they worked, then disassembled them only to slip through a “loophole” by shipping the pieces abroad. To say that no infringement occurred because the final bolts were tightened overseas was, in his view, to reward a manufacturer for an artificial, last-step evasion of a valid patent. The dissent would have read “makes” functionally, to cover a manufacturer that does everything but the trivial final assembly within the United States.

The split thus crystallized the enduring tension in extraterritoriality doctrine: the majority’s bright-line, territorial reading versus the dissent’s purpose-driven, anti-circumvention reading. That same tension would later animate the §271(f) cases the decision spawned.

The congressional sequel

Deepsouth is remembered less for what it decided than for what it provoked. In 1984, Congress enacted 35 U.S.C. §271(f), expressly to overturn the result. The new provision made it infringement to “suppl[y] … from the United States” the “components of a patented invention” for “combination” abroad in a manner that would infringe if done domestically—precisely the kit-export maneuver Deepsouth had blessed. Section 271(f)(1) reaches the supply of “all or a substantial portion” of the components with intent to induce combination; §271(f)(2) reaches even a single specially adapted, non-staple component. Every modern dispute over the extraterritorial reach of patents—Microsoft v. AT&T on software masters, Life Technologies v. Promega on single components, and the damages question in WesternGeco—traces back to the gap Deepsouth identified and Congress filled.

Open questions

  • How far did §271(f) actually close the gap? The statute reaches component supply, but Microsoft later held that foreign-made copies are not “supplied from the United States,” leaving residual space for the Deepsouth logic.
  • Does the territorial reading of “makes” still govern §271(a)? Deepsouth’s core holding about domestic assembly remains good law for §271(a) even as §271(f) supplements it.
  • What is a “combination” for these purposes? The line between making unpatented parts and making the patented whole continues to matter for kit-based and modular products.
  • How should courts treat near-complete domestic assembly? Blackmun’s functional concern resurfaces whenever a manufacturer performs all but a final, trivial step inside the United States.

Implications

  • Deepsouth established the baseline territorial rule—U.S. patents do not reach foreign making, using, or selling—that still frames every extraterritoriality dispute.
  • It is the direct legislative cause of §271(f); reading the statute without Deepsouth misses the gap the provision was built to close.
  • The case shows the Court’s recurring posture: identify a loophole, decline to fill it by interpretation, and leave expansion of the patent monopoly to Congress.
  • The majority’s “remedy lies in foreign patents” reasoning remains the standard answer to those seeking U.S. enforcement against foreign conduct.
  • The 5-4 split previews the form-versus-substance debate that continues to divide courts applying §271(f) today.

Frequently asked questions

Why did exporting a complete set of parts not infringe? Because a combination patent is infringed only by “making” the assembled invention, and Deepsouth assembled the machines abroad. Making the unpatented parts in the U.S. was not making the patented combination.

Is Deepsouth still good law? Its interpretation of “makes” under §271(a) remains valid, but Congress superseded its practical result for component exports by enacting §271(f) in 1984.

What is the connection to modern §271(f) cases? Section 271(f) exists because of Deepsouth. Later decisions like Microsoft v. AT&T and Life Technologies v. Promega interpret the statute Congress passed to overturn this case.

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