Background
Johnson & Johnston Associates owned a patent covering a method of manufacturing printed circuit boards (PCBs). The patented method involved the step of laminating a thin sheet of copper foil to a thicker piece of aluminum, which served as a protective and conductive substrate during board fabrication. The aluminum substrate was eventually stripped away after the copper foil had been attached to the circuit board. Crucially, the patent’s specification mentioned that steel or other materials could be used instead of aluminum as the substrate, but the patent’s claims were written exclusively in terms of aluminum substrates.
R.E. Service Company used a similar process, but substituted steel for aluminum as the substrate material. Johnson & Johnston sued for infringement and, when R.E. Service pointed out that steel was not claimed, argued that the steel substrate was equivalent to the claimed aluminum substrate under the doctrine of equivalents. The doctrine of equivalents is a legal principle that prevents infringers from avoiding infringement by making minor, insubstantial substitutions from the literal claim language. The district court agreed that equivalence existed and found infringement. R.E. Service appealed, and the Federal Circuit ordered en banc review of the disclosure-dedication question.
The Court’s Holding
The Federal Circuit reversed in a per curiam en banc opinion joined by twelve of thirteen judges. The court adopted what is known as the disclosure-dedication doctrine: when a patent specification discloses specific subject matter — such as alternative materials, embodiments, or design choices — but the patentee fails to claim that subject matter, it is dedicated to the public. A patentee who chooses not to claim a disclosed alternative cannot later assert, through the doctrine of equivalents, that the alternative infringes what was actually claimed.
The court grounded this rule in fundamental principles of patent law. Patents provide a quid pro quo — the inventor receives a limited monopoly in exchange for public disclosure. When an inventor discloses alternatives in the specification, the public is entitled to rely on those alternatives being available. If alternatives are disclosed but not claimed, competitors can reasonably treat them as open to use. Allowing the doctrine of equivalents to recapture unclaimed but disclosed subject matter would violate this reasonable public reliance and would effectively allow a patentee to expand claim scope beyond what was actually claimed.
The rule confirmed by the en banc court was objective in nature: the patentee’s subjective intent in failing to claim the disclosed alternative was irrelevant. What mattered was the objective fact of disclosure without claiming. Because the ‘050 patent’s specification disclosed steel as an alternative substrate but the claims were limited to aluminum, the steel substrate embodiment had been dedicated to the public and could not be reached by the doctrine of equivalents.
Key Takeaways
- The disclosure-dedication doctrine bars the doctrine of equivalents for subject matter that was disclosed in the patent specification but was not claimed — such alternatives are dedicated to the public.
- An inventor who chooses not to claim a disclosed alternative cannot use the doctrine of equivalents to assert that alternative against competitors who copy it — the choice not to claim is binding.
- The disclosure-dedication rule is objective — the patentee’s intent or inadvertence in not claiming the subject matter is irrelevant; what matters is the fact of disclosure without claiming.
- Patent drafters must carefully identify all alternatives and embodiments they wish to protect and include them in the claims — merely mentioning alternatives in the specification does not preserve claim coverage over those alternatives.
- This en banc decision significantly constrained the scope of the doctrine of equivalents by carving out a large category of potential equivalents — disclosed-but-unclaimed subject matter — that the doctrine cannot reach.
Why It Matters
Johnson & Johnston v. R.E. Service is a landmark Federal Circuit decision on the relationship between patent specifications, claims, and the doctrine of equivalents. Before this decision, there was some uncertainty about whether disclosed-but-unclaimed alternatives could be reached through equivalents claims. The en banc court’s near-unanimous adoption of the disclosure-dedication doctrine resolved that uncertainty clearly: unclaimed alternatives in the specification are public domain, regardless of equivalence.
This decision has profound practical consequences for patent drafting and litigation. For patent prosecutors, it means that the specification’s disclosure of alternatives must be matched by actual claim coverage of those alternatives — or those alternatives will be lost. For litigants defending against infringement claims, it provides a powerful tool: if the patent specification itself discloses what the defendant is doing, and that subject matter was not claimed, the claim is barred by the disclosure-dedication doctrine regardless of equivalence. The rule creates a strong incentive for careful and comprehensive claim drafting and discourages the use of the doctrine of equivalents as a tool for expanding claim scope beyond deliberate drafting choices.