IP Law Daily, PATENT—D. Mass.: Equitable estoppel not shown in stroller patent dispute, (Jun 26, 2025)

By Kevin M. Finson, J.D.

Summary judgment based on equitable estoppel was denied because genuine questions of material fact existed as to whether the plaintiff engaged in misleading conduct and whether the defendant reasonably relied on such conduct.

Patent infringement claims brought by a seller of strollers against a competitor were not barred by equitable estoppel, the U.S. District Court in Boston has held. At least at the summary judgment stage, it was not shown that the seller engaged in misleading conduct or that this conduct was relied upon by the competitor (Baby Jogger, LLC v. Monahan Products, LLC, No. 1:24-cv-11582-ADB (D. Mass. June 24, 2025)).

Baby Jogger, LLC (Baby Jogger) was the owner of U.S. Patents Nos. No. 8,955,869 (the ’869 patent), 9,403,550 (the ’550 Patent) 11,192,568 (the ’568 patent), 11,505,231 (the ’231 patent), and 11,878,729 (the ’729 patent), all of which related to baby strollers. In December of 2015 Baby Jogger and its parent company at the time engaged in correspondence with Monahan Products, LLC, d/b/a UPPAbaby (UPPAbaby) in which they alleged that UPPAbaby’s Vista Stroller and other products infringed their patents, and UPPAbaby’s counsel responded that Baby Jogger’s parent company was engaging in unfair business practices. Nothing else was done by either party for some eight years, after which Baby Jogger brought suit for infringement. UPPAbaby moved for summary judgment on the grounds that the claims were barred by equitable estoppel.

Misleading conduct. On the first element of equitable estoppel, the court found that the record could potentially support, but did not require, the inference that Baby Jogger’s decision not to litigate for eight years was misleading. Based on the letters and emails in the record, a reasonable jury could find either that Baby Jogger had abandoned the issue or that it had narrowed the issue to particular products, so summary judgment was not appropriate.

Reasonable reliance. Additionally, the court found that even if there had been misleading conduct there was no showing of reliance on the part of UPPAbaby. There was no showing that UPPAbaby’s decisions to continue selling the accused products or to refrain from bringing suit against Baby Jogger for unfair business practices were made based on Baby Jogger’s inaction.

The court denied the motion for summary judgment, noting that UPPAbaby was free to raise the equitable estoppel issue again at a later stage of the proceedings on a more developed record, if appropriate.

The Case is No. 1:24-cv-11582-ADB.

Judge: Burroughs, A.

Attorneys: Gregory Joseph Carlin (Meunier Carlin & Curfman LLC) for Baby Jogger. Craig R. Smith (Lando & Anastasi, LLP) for Monahan Products, LLC.

Companies: Monahan Products, LLC

Cases: Patent MassachusettsNews