In a closely watched construction-technology patent dispute, Hilti Aktiengesellschaft and Specified Technologies, Inc. (STI) filed a joint stipulation of dismissal on August 7, 2024, bringing Case No. 1:22-cv-01248 before the Delaware District Court to a close after 685 days of litigation. Hilti dismissed with prejudice all claims of infringement under six U.S. patents—Nos. 10,267,036, 10,774,528, 10,596,399, 10,610,711, 10,641,417, and 11,137,091—while STI simultaneously dismissed with prejudice its counterclaims under U.S. Patent Nos. 9,157,232 and 10,143,868. Each side agreed to bear its own costs, expenses, and attorneys’ fees, and the dismissal expressly preserved two parallel proceedings between the same parties.

This outcome carries significant strategic weight for IP professionals operating in the passive fire protection and firestopping technology space. The mutual, prejudice-laden dismissal—while leaving no public damages award or injunction on record—signals a negotiated resolution likely tied to the broader commercial relationship and ongoing parallel litigations. Patent attorneys, in-house IP teams, and R&D leaders developing penetration seal or through-penetration firestop systems should study this case’s multi-patent assertion strategy and the continued dispute landscape it reflects.

Case Overview

The Parties

The Patents at Issue

The patents at issue in this dispute collectively cover passive fire protection systems—specifically, firestopping devices and assemblies used to seal openings and penetrations in walls, floors, and ceilings through which pipes, cables, or conduits pass, preventing the spread of fire and smoke in buildings. Key claims across patents such as US10267036B2, US10774528B2, US10596399B2, US10610711B2, US10641417B2, and US11137091B2 address structural configurations, materials, and installation mechanisms for through-penetration firestop systems. The products at the center of the dispute—including STI’s SpeedFlex®, Track Top Gasket (TTG), and Part Number TTG350F—are commercial firestopping components used in building construction and code-compliant fire-rated assemblies.

• • US10663090B2
• • US10641417B2
• • US10295088B2
• • US10610711B2
• • US11242946B2
• • US11137091B2
• • US10596399B2
• • US10267036B2
• • US10774528B2

Legal Representation

Plaintiff Counsel: Young Conaway Stargatt & Taylor, LLP (lead: Alexis Stombaugh)
Defendant Counsel: Fox Rothschild LLP (lead: Austen C. Endersby)

Litigation Timeline & Procedural History

This case was filed on September 22, 2022, in the U.S. District Court for the District of Delaware—a jurisdiction frequently selected for patent litigation due to its experienced judiciary, well-developed patent case law, and efficient docket management. Presided over by Chief Judge Christopher J. Burke, the matter proceeded as a first-instance district court action, meaning the parties engaged at the trial level without any intervening appellate or administrative review in this docket. The case was categorized as a patent infringement action, with Hilti asserting six patents against STI’s commercial firestopping products and STI counter-asserting two patents of its own, creating a bilateral multi-patent dispute typical of competitive technology markets.

The case ran for 685 days—approximately 22.5 months—before closing on August 7, 2024, via a stipulated dismissal under Federal Rule of Civil Procedure 41(a)(1)(A)(ii). This duration reflects a prolonged pretrial phase likely involving claim construction briefing, discovery, and potential settlement negotiations, but the matter resolved short of trial. Notably, the dismissal was carefully structured: Hilti’s infringement claims and STI’s counterclaims were dismissed with prejudice, foreclosing re-litigation of those specific claims, while remaining counterclaims were dismissed without prejudice. The parties also explicitly preserved their rights in two parallel Delaware actions—Civil Action Nos. 22-cv-1383-CJB and 23-cv-0244-CJB—signaling that the broader competitive patent dispute between Hilti and STI remains active.

The Verdict & Legal Analysis

Outcome

The case was resolved through a joint stipulation of dismissal filed pursuant to Fed. R. Civ. P. 41(a)(1)(A)(ii), with no judicial finding of infringement, validity, or damages entered on the record. Hilti dismissed with prejudice all six of its patent infringement claims, and STI dismissed with prejudice its two counterclaims for infringement under U.S. Patent Nos. 9,157,232 and 10,143,868; remaining counterclaims by both parties were dismissed without prejudice. Each party agreed to bear its own costs, expenses, and attorneys’ fees, and no injunctive relief or damages award was publicly disclosed.

Verdict Cause Analysis

The stipulated dismissal structure reveals several important legal and strategic dynamics that shaped how this infringement action was resolved.

• The with-prejudice dismissal of Hilti’s six infringement claims operates as an adjudication on the merits, permanently barring Hilti from re-asserting those specific claims against STI under the same patents in any future action arising from the same conduct.
• STI’s with-prejudice dismissal of its counterclaims under U.S. Patent Nos. 9,157,232 and 10,143,868 similarly extinguishes those specific counterclaims, reflecting a mutual concession of the direct claims at issue in this docket.
• The without-prejudice dismissal of remaining counterclaims by both parties preserves flexibility for those issues to be raised in future proceedings or in the two expressly preserved parallel actions, indicating that not all contested IP rights were settled.
• The cost-sharing arrangement—each party bearing its own fees and expenses—is consistent with a negotiated resolution rather than a court-ordered outcome, and no sanctions, fee-shifting, or exceptional case findings were recorded.

Legal Significance

1. The mutual with-prejudice dismissal effectively removes this specific set of six Hilti patents and two STI patents from re-litigation between these parties, narrowing the IP arsenal available in their ongoing Delaware dispute without resolving broader portfolio questions.
2. The explicit carve-out preserving Civil Action Nos. 22-cv-1383-CJB and 23-cv-0244-CJB underscores that stipulated dismissals in multi-docket patent disputes can be surgically tailored, offering a model for parties managing complex, multi-case litigation to resolve individual dockets strategically without prejudicing parallel claims.
3. Because the case terminated before any claim construction order or merits ruling, the patents-in-suit (including US10267036B2, US10774528B2, US10596399B2, US10610711B2, US10641417B2, and US11137091B2) retain their full presumption of validity and may be asserted against third parties, making FTO analysis of these patents critical for competitors in the firestopping market.

Strategic Takeaways

For Patent Attorneys:

• When structuring stipulated dismissals in multi-docket patent cases, draft with surgical precision—specifying which claims are dismissed with versus without prejudice and expressly identifying preserved parallel proceedings, as done here, to avoid inadvertently extinguishing client rights.
• The bilateral assertion strategy in this case (Hilti asserting six patents; STI counter-asserting two) is a common escalation tactic in competitive technology markets; counsel should audit client portfolios proactively to identify defensive counterclaim assets before litigation commences.
• The absence of any claim construction record from this docket means the Hilti patents-in-suit have no binding judicial interpretation of their claims, which both preserves and complicates future assertion strategy—prosecution history and intrinsic record will be dispositive in any subsequent action.

For IP Professionals:

• In-house IP teams at firestopping and passive fire protection companies should monitor the two remaining Hilti v. STI Delaware actions (Nos. 22-cv-1383-CJB and 23-cv-0244-CJB), as any claim construction rulings or verdicts there will have direct implications for portfolio valuation and licensing strategy across the firestopping sector.
• The with-prejudice dismissal of claims under six Hilti patents does not affect those patents’ enforceability against other market participants; IP teams at competitors should treat US10267036B2, US10774528B2, US10596399B2, US10610711B2, US10641417B2, and US11137091B2 as live enforcement risks and conduct targeted FTO reviews.

For R&D Teams:

• R&D teams developing through-penetration firestop systems, track gaskets, or flexible firestopping products should conduct freedom-to-operate analysis against the nine patents identified in this case before commercializing new designs, as these patents remain valid and enforceable against third parties.
• The products at the center of this dispute—SpeedFlex®, Track Top Gasket (TTG), and Part Number TTG350F—represent specific commercial implementations that triggered multi-patent assertions; engineering teams should document design decisions and prior art searches contemporaneously to support any future invalidity or non-infringement defense.