Sto Cote Products Inc v. Ez Ice Rinks

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Sto-Cote Products, Inc. dba NiceRink (Illinois)
  • Defendant: EZ Ice Rinks, Inc. (Massachusetts)
  • Plaintiff’s Counsel: Hibbs Law, LLC
• Case Identification: 1:25-cv-15739, N.D. Ill., 12/29/2025
• Venue Allegations: Plaintiff Sto-Cote alleges venue is proper because Defendant EZ Ice Rinks conducts regular business in the district through direct sales and retailers, is subject to personal jurisdiction, and a substantial part of the events giving rise to the claim (pre-suit communications) occurred in the district.
• Core Dispute: Plaintiff seeks a declaratory judgment that its outdoor ice rink products do not infringe Defendant’s patent related to self-standing ice rink structures.
• Technical Context: The dispute involves kits for constructing temporary, backyard ice skating rinks, a market segment focused on seasonal, non-permanent installations for residential and community use.
• Key Procedural History: The complaint details over two years of pre-suit communications, including cease-and-desist letters from the defendant. Notably, the plaintiff filed for an Ex-Parte Re-Examination of the patent-in-suit, which concluded with a majority of the original claims being amended, canceled, or replaced. This re-examination history, particularly any narrowing of claim scope, may be central to the non-infringement arguments.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 11,712,617 - "ICE SKATING RINK STRUCTURE AND METHOD"

The Invention Explained

• Problem Addressed: The patent's background section describes the difficulty and labor involved in constructing conventional outdoor ice rinks, which often require tools, hardware (e.g., stakes, lumber, screws), and penetration of the underlying ground, making them unsuitable for surfaces like tennis courts or turf fields ('617 Patent, col. 2:6-51).
• The Patented Solution: The invention is a portable, self-standing ice rink kit that does not require ground penetration or additional tools for assembly ('617 Patent, col. 1:15-18). The system uses a perimeter formed by interlocking side boards, which are held upright by board holding members. Tension members, such as straps, traverse the rink area and attach to the board holding members on opposite sides, using the eventual weight of the water and ice to create a stable, self-supporting structure ('617 Patent, col. 3:1-11; Fig. 1).
• Technical Importance: The described approach aims to simplify rink installation for average consumers and allow setup on a wider variety of surfaces without causing damage ('617 Patent, col. 4:17-30).

Key Claims at a Glance

• The complaint identifies independent claim 1 as a representative asserted claim (Compl. ¶72). It also notes that defendant has alleged infringement of independent claims 38, 45, 74, 102, 103, and 104 (Compl. ¶30). The analysis focuses on claim 1.
• Essential elements of independent claim 1 include:
  • A kit for constructing a self-standing ice skating rink structure
  • Side boards configured to collectively define an area, with connection elements at each end
  • Board holding members configured to releasably secure the side boards in a vertical orientation
  • Tension members configured to be attached to at least one board holding member and traverse the area
  • Wherein at least one of the board holding members comprises a receptacle
  • And at least one of the tension members is configured to be attached to the receptacle
• The complaint does not explicitly reserve the right to assert dependent claims but seeks a declaration of non-infringement of "any valid or enforceable claim" of the '617 patent (Compl. ¶1).

III. The Accused Instrumentality

Product Identification

• The complaint identifies "NiceRink's strappable SPIKELESS brackets and straps" and, more generally, "spikeless versions of its rink brackets/kits" as the products accused of infringement by the defendant (Compl. ¶8, ¶42).

Functionality and Market Context

• The complaint describes Plaintiff Sto-Cote as a provider of outdoor ice rink products and services for over 30 years, serving homeowners, businesses, and municipalities (Compl. ¶2, ¶44).
• The complaint does not provide sufficient detail for analysis of the specific technical functionality or structure of the accused products. The core of the non-infringement argument centers on the alleged absence of a specific claimed component, rather than a detailed description of the product's operation (Compl. ¶73).

IV. Analysis of Infringement Allegations

The complaint seeks a declaratory judgment of non-infringement. The following table summarizes the plaintiff’s central argument for why its products do not meet the limitations of the asserted claims, using claim 1 as an example.

'617 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: The primary dispute appears to be definitional. The case may turn on the proper legal construction of the term "receptacle," particularly in light of claim amendments made during the ex parte re-examination initiated by Sto-Cote (Compl. ¶24, ¶28, ¶73). The complaint alleges that this limitation is present in every asserted claim, suggesting this is a dispositive, case-wide issue (Compl. ¶74).
  • Technical Questions: A central factual question will be whether the accused "strappable SPIKELESS brackets" contain a component that performs the function of and has the structure of the claimed "receptacle," once that term is properly construed by the court. The complaint provides no technical details or drawings of the accused product to facilitate this comparison.

No probative visual evidence provided in complaint.

V. Key Claim Terms for Construction

• The Term: "receptacle"
• Context and Importance: This term is the explicit basis for Sto-Cote's non-infringement argument (Compl. ¶73). Its definition is critical because if the accused products are found to lack a "receptacle" as construed by the court, there can be no literal infringement of any asserted claim. Practitioners may focus on this term because Sto-Cote's complaint directly links its meaning to narrowing amendments made during prosecution and re-examination, suggesting a potentially strong prosecution history estoppel argument.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The claims themselves recite the term without extensive structural definition, stating only that it is part of a "board holding member" and is where a "tension member is configured to be attached" ('617 Patent, col. 17:47-49). A party might argue this requires only a feature that receives and secures a tension member.
  • Evidence for a Narrower Interpretation: The specification repeatedly describes the board holding member as having a "U-shaped slot or receptacle area for holding at least one board" and a separate "aperture or receptacle for which to attach a tension member" ('617 Patent, col. 2:24-28). The detailed description further identifies the receptacle for the tension member as an "aperture (or loop or ring structure or receptacle or receiver) 17 for accepting and retaining the tension members" ('617 Patent, col. 8:3-5). A party could argue these specific embodiments limit the term to a distinct opening or structure separate from where the board itself is held.

VI. Other Allegations

• Indirect Infringement: Sto-Cote seeks a declaration that it does not induce or contribute to the infringement of any enforceable claim of the '617 Patent (Compl. ¶78).
• Willful Infringement: The complaint states that EZ Ice has repeatedly accused Sto-Cote of willful infringement and threatened to seek treble damages (Compl. ¶19, ¶30, ¶39). Sto-Cote's declaratory judgment action seeks to preemptively defeat any such claim by establishing non-infringement.

VII. Analyst’s Conclusion: Key Questions for the Case

This case appears to center on a focused, dispositive legal and technical question, amplified by a significant procedural history. The key questions for the court will likely be:

• A core issue will be one of claim construction: What is the proper scope of the term "receptacle" as used in the asserted claims, particularly after being subject to an ex parte re-examination where, according to the complaint, claims were significantly amended?
• A subsequent evidentiary question will be one of technical comparison: Does the plaintiff's "strappable SPIKELESS bracket" system include a structure that meets the court's construction of the term "receptacle," or does it achieve a similar result using a technically distinct, non-infringing design?