Background
Float’N’Grill LLC held a patent on a floating apparatus designed to support a portable grill over water, allowing users to cook while floating in a pool or lake. The original patent described a single embodiment in which the grill is attached to the float using a plurality of magnets — multiple magnets were described as a necessary structural element for removably securing the grill.
After issuance, Float’N’Grill filed a reissue patent application seeking to broaden its claims. Reissue under 35 U.S.C. § 251 allows patentees to correct errors in an issued patent, including by broadening claims, but only if the reissue claims are directed to “the same invention” disclosed in the original patent. Float’N’Grill’s proposed reissue claims were broader: some required zero magnets, some required only one magnet, and one made magnet attachment optional altogether — all departures from the original patent’s magnet-based embodiment. The USPTO’s Patent Trial and Appeal Board (PTAB) rejected the application, and Float’N’Grill appealed to the Federal Circuit.
The Court’s Holding
The Federal Circuit affirmed. The court applied the “original patent” requirement of § 251: for a reissue to be valid, the original patent must explicitly and unequivocally disclose the invention as recited in the proposed reissue claims. The court found that Float’N’Grill’s original patent disclosed magnets as a necessary, critical element of the floating grill apparatus — every described embodiment used multiple magnets as the means of removable attachment, and nothing in the specification suggested that magnets could be omitted or replaced.
The court held that when a patentee’s original disclosure treats an element as essential to the invention, a reissue claim that eliminates or replaces that element is not directed to the “same invention.” Reissue cannot be used to claim alternatives to essential elements that were never disclosed in the original application. Because the proposed broader claims encompassed grill-attachment methods that were not described or suggested in the original patent, they failed the § 251 original patent requirement and the USPTO properly rejected them.
Key Takeaways
- Reissue claims must be directed to the same invention explicitly disclosed in the original patent — they cannot encompass undisclosed alternatives to elements that the original specification treated as necessary, critical, or essential.
- If a patent’s specification describes only one way of achieving a function (e.g., magnetic attachment), a reissue cannot broaden the claims to cover non-magnetic alternatives not mentioned in the original disclosure.
- The § 251 “original patent” requirement is a meaningful limitation on broadening reissue; it is not satisfied by arguing that the broader concept is obvious or that competitors use equivalent structures.
- Patent applicants should draft original specifications broadly enough to support alternative embodiments of every critical element if they may later want to pursue broader claims via reissue or continuation applications.
Why It Matters
In re Float’N’Grill clarifies the limits of reissue practice as a tool for broadening patent protection after issuance. Reissue is sometimes called a “second chance” for patentees who claimed too narrowly, but this decision makes clear that the second chance is limited to inventions actually described in the original filing — it cannot be used to expand coverage to embodiments the inventor never disclosed. Companies that discover post-issuance that their patents are narrower than they thought cannot use reissue to rewrite the invention; the original specification governs what can be reclaimed.
For patent prosecutors, the case underscores the importance of including multiple embodiments and alternative implementations in the original specification. A lean specification that describes only a single preferred embodiment may foreclose reissue as a broadening strategy. Particularly where an element is described as integral to the invention — even implicitly, by virtue of its presence in every example — eliminating or substituting that element in a reissue claim will likely fail the § 251 same-invention requirement.