Zeta Global Corp. v. Maropost Marketing Cloud, Inc.

Background

Zeta Global alleged that Maropost infringed U.S. Patent Nos. 7,536,439 and 8,108,475. The patents concern methods for handling messages generated when email delivery fails, classifying those messages into failure types, and deciding whether an email address should be marked invalid. The ’475 Patent is a continuation of the ’439 Patent, and the parties agreed that Claim 1 of each patent was representative.

The parties presented proposed meanings for “deliver” and “failure type” in a claim-construction proceeding. Claim construction is the court’s determination of what disputed patent terms mean. The parties’ submissions also placed the meaning of “failure message” in dispute. Maropost argued that “deliver” should have a narrower technical meaning and argued that “deliver” and “failure type” were indefinite. A patent term is indefinite when the patent does not inform a skilled person about the scope of the invention with reasonable certainty.

Claim Construction

The court construed “deliver” to mean “change of control.” It reasoned that the claims used “deliver” in its ordinary sense to describe a transfer of control over an email message between entities. The court rejected Maropost’s proposed narrower definition, which referred to transferring a message from a computerized mail-handling transport service to a recipient’s inbox or another recipient resource.

The court construed “failure type” to mean “a classification of a failure message.” It relied on the claims’ references to classifying failure messages under rules and on the specification’s examples, including “Server Down,” “Spam,” “Virus,” “Bad Domain,” and “Out-of-Office.”

Indefiniteness

The court held that “deliver” was not indefinite under the construction “change of control.” The claims and specification provided reasonable certainty about the term’s scope, including because they covered actions involving failure messages generated before or after delivery to the intended recipient.

The court also held that “failure type” was not indefinite. The patents described applying rules to categorize failure messages and gave examples of failure types. The court rejected Maropost’s argument that several examples in the specification created an unclear boundary between covered and uncovered failure types.

The court found “failure message” indefinite in the ’439 Patent. Claim 1 described a failure message received when an Internet service provider could not deliver an email to a recipient. Claim 6, which depended on Claim 1, described that failure message as created after delivery. The court found those meanings contradictory and concluded that a skilled person could not determine the scope of the term with reasonable certainty. The court stated that “failure message” was not indefinite in the ’475 Patent because the relevant claims did not contain the same contradiction.

Disposition

The court concluded that “failure message” was indefinite in the ’439 Patent and that the asserted claims containing that term were invalid under 35 U.S.C. § 112. It dismissed Zeta’s infringement claims for Claims 1, 2, 7, 11, and 12 of the ’439 Patent in Count 4 of the complaint. It construed the remaining disputed terms as described above.

The parties were directed to file a joint letter by July 20, 2021, proposing next steps, including any proposal for summary-judgment briefing.