IP Hot Topic: Causam Enterprises, Inc. v. ITC: An Assignment for “Continuations” Did Not Include “Continuations-in-Part”

Summary

In Causam Enterprises, Inc. v. ITC, No. 23-1769 (Fed. Cir. Oct. 15, 2025), the Federal Circuit addressed whether Causam was the owner of the asserted patent and, thus, had Article III standing. The central issue was whether an early inventor assignment included rights to continuation-in-part applications. The Court held it did not, because the assignment identified “continuations” but omitted “continuations-in-part.” As a result, the inventor retained rights in continuation-in-part applications and their descendants, and subsequently assigned those rights to Causam. Ultimately, however, the Federal Circuit dismissed the appeal as moot because, in a companion appeal, the PTAB’s decision finding the asserted claim invalid was affirmed.

Background

At the International Trade Commission, Causam asserted U.S. Patent No. 10,394,268 against importers of accused “smart” thermostat devices. The ’268 patent is a continuation of another continuation application, which in turn was a continuation-in-part of an earlier series of priority applications. The ’268 patent names Causam as the assignee on its face, and there was a 2014 assignment from the inventor to Causam that expressly identified “continuations in whole or part.”

The Respondents at the ITC argued Causam did not own the ’268 patent because the inventor had no rights left to assign in 2014. In 2007, the inventor executed an assignment to another company, America Connect, that conveyed the “invention” of the earliest priority application and “all divisions, reissues, continuations, and extensions thereof.” The ITC Administrative Law Judge (ALJ) agreed with the Respondents and held that Causam did not own the ’268 patent. The ALJ found that the 2007 assignment assigned “all progeny” of the earliest priority application, including the ’268 patent, to America Connect. The ALJ also found no infringement of the ’268 patent. The ITC adopted the ALJ’s noninfringement finding, but declined to adopt the holding that Causam did not own the ’268 patent.

Federal Circuit’s Analysis

The key issues on appeal were: (1) whether Causam was the owner of the ’268 patent and, thus, had standing, and (2) whether claim 1 was infringed. The infringement issue was rendered moot after the Federal Circuit, in a parallel appeal, affirmed the PTAB’s decision finding the asserted claim invalid. However, the Federal Circuit still addressed the ownership issue and confirmed that Causam owned the ’268 patent.

The Court focused on whether the 2007 assignment covered a continuation-in-part application and its descendants, culminating in the ’268 patent. If it did, the inventor had nothing left to assign in 2014. If it did not, the 2014 assignment to Causam was effective.

The Court noted that ownership of the ’268 patent was a purely legal question based on the record evidence, namely, the assignments. Then applying general principles of contract law, the Court emphasized that contract terms must be interpreted according to their plain language, and courts may not insert terms the parties never agreed to.

Turning to the record evidence, the Court noted that the 2007 assignment identified “continuations,” but not “continuations-in-part.” Citing the Patent Office’s Manual of Patent Examining Procedure (MPEP) and standard patent practice, the Court emphasized that continuations-in-part and continuations are widely understood to be different and in fact legally distinct, in a way relevant to assignment. The Court explained that reading “continuations” to include “continuations-in-part” would amount to inserting words that the parties did not agree to. The Court noted that an inventor may well wish to assign away continuations of an invention but keep the rights to continuations-in-part—and the new matter disclosed in the continuations-in-part. Further, for assignments, the MPEP sets out that for a continuation, recordation of assignment of the parent is effective as to the child, but the same is not true of a continuation-in-part. The Court also distinguished prior precedent by noting that in Causam there were no interrelated agreements indicating that the recited “continuations” included continuations-in-part.

Accordingly, the Court concluded that the 2007 assignment did not reach the continuation-in-part lineage that included the ’268 patent, and thus, the inventor remained the rightful owner. Thus, the inventor’s subsequent 2014 assignment to Causam validly conveyed the rights in the ’268 patent, satisfying the standing requirement.

Recommendations for Practitioners

The Causam decision provides important lessons about patent assignments, title risk, and downstream developments. Below are some recommendations to help minimize title disputes and maximize enforceability.

1. Be deliberate and precise in assignment language.

Small differences in wording—like omitting “continuations-in-part”—can have significant consequences on patent ownership. To avoid ambiguity, the assignment should explicitly reference “continuations-in-part” in the grant when the parties intend to convey continuations-in-part and any new subject matter disclosed therein. Similarly, if the parties intend to convey all subsequently filed applications within a specific priority chain, the assignment can explicitly identify “all applications that claim the benefit of” a referenced patent application. Without other supporting evidence, courts likely will not rewrite contracts to add omitted assigned subject matter.

2. Ownership due diligence is important.

Whether conducting due diligence as a part of an acquisition or a pre-suit investigation, parties should closely review the assignment history and chain of title of the relevant patents. This review should include all inventor assignments, employment agreements, settlement agreements, merger documents, licenses, and any other intervening transfers. Particular attention should be paid to whether assignments may have inadvertently omitted downstream rights or reserved rights in certain types of applications, such as continuations-in-part or newly developed subject matter. As demonstrated in Causam, patent ownership (or exclusive licensee status) is a threshold issue for standing in patent litigation.

3. Execute new assignments for continuations-in-part.

Even if a parent assignment appears to cover future continuations-in-part or later developed subject matter, executing new or confirmatory assignments for such applications can help eliminate any ambiguity about ownership. By proactively executing follow-on assignments at or soon after the filing of the continuation-in-part, parties ensure that title remains clear. Even in cases where the original assignee believes it has all rights, a confirmatory assignment reduces the risk of future challenge.

Takeaway: Patent title can become fractured as families grow. To protect enforceability, parties must draft assignments with precision, verify ownership carefully, and preferably use fresh assignments for each new development—particularly for continuations-in-part. A clean chain of title is as important as the strength of the claims themselves.