Geissele Automatics LLC WHG Properties LLC v. Lewis Machine & Tool Co

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Geissele Automatics, LLC (Pennsylvania) and WHG Properties, LLC (Pennsylvania)
  • Defendant: Lewis Machine & Tool Company (Illinois)
  • Plaintiff’s Counsel: Fox Rothschild LLP
• Case Identification: 4:19-cv-04030, C.D. Ill., 02/12/2019
• Venue Allegations: Venue is alleged to be proper in the Central District of Illinois because the Defendant is alleged to have a principal place of business in the district.
• Core Dispute: Plaintiffs allege that Defendant’s two-stage trigger assembly for firearms infringes a patent related to the mechanical design of such trigger systems.
• Technical Context: The technology concerns multi-stage trigger mechanisms for AR-15/M16-platform rifles, a market where precision, reliability, and safety are critical for both civilian and military applications.
• Key Procedural History: The complaint alleges that Plaintiffs sent a cease and desist letter to the Defendant on December 17, 2018. This event establishes a date of alleged actual notice, which is foundational to the claim for willful infringement.

Case Timeline

Date	Event
2008-01-17	’338 Patent Priority Date
2009-10-13	’338 Patent Issue Date
2018-12-17	Plaintiffs send cease and desist letter to Defendant
2019-02-12	Complaint Filing Date

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

U.S. Patent No. 7,600,338 - "Multi-Stage Trigger for Automatic Weapons"

• Patent Identification: U.S. Patent No. 7,600,338, "Multi-Stage Trigger for Automatic Weapons", issued October 13, 2009.

The Invention Explained

• Problem Addressed: The patent describes problems with prior art two-stage triggers, including the tendency for adjustment set screws to become loose after prolonged use, creating an unsafe or inoperable condition (’338 Patent, col. 1:43-49). It also notes that designs relying on flat-surface-to-flat-surface contact between moving parts are difficult to manufacture consistently, leading to unreliable trigger pull (’338 Patent, col. 1:55-65). A further problem identified is the lack of a secondary safety sear in some aftermarket triggers, which could prevent accidental discharge if the primary sear fails (’338 Patent, col. 2:24-30).
• The Patented Solution: The invention claims to solve these problems by providing a two-stage trigger that does not use set screws for adjustment. Instead, trigger pull weight is adjusted by swapping pre-calibrated disconnector springs (’338 Patent, col. 2:15-19; Fig. 8). To ensure consistent sear engagement, the design uses a non-linear surface (a partial radius) on the trigger stop, which creates a precise "line contact" with the flat face of the disconnector, a configuration less susceptible to manufacturing variances (’338 Patent, col. 2:1-10; Fig. 5). The design also incorporates a secondary safety sear to prevent the hammer from falling if the primary sear breaks (’338 Patent, col. 2:28-30).
• Technical Importance: This approach provides a robust, adjustable, and safe two-stage trigger that can be installed without custom fitting and maintains consistent performance over time. (’338 Patent, col. 1:49-54).

Key Claims at a Glance

• The complaint asserts independent claim 7. (Compl. ¶9).
• The essential elements of independent claim 7 include:
  • An assembly of a spring-loaded trigger, disconnector, and hammer.
  • The trigger having a "trough" to house the disconnector.
  • The trigger having a "trigger sear hook" with an "aperture" through it for the disconnector to operate and exit the front side.
  • A hammer pivotally connected to the firearm.
  • The trigger and hammer having "engagement means" to hold the hammer in a cocked position.
  • The disconnector having a "contact means" for interacting with the hammer to create the second-stage resistance and a spring to hold it in position.
  • The hammer having a "contact means" for contacting the disconnector's contact means.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The "Two-Stage Trigger Group" manufactured and sold by Defendant Lewis Machine & Tool Company (the "Accused Device") (Compl. ¶8).

Functionality and Market Context

• The complaint alleges the Accused Device is a multi-stage trigger for automatic weapons (Compl. ¶9). Its functionality is described as comprising a spring-loaded trigger, disconnector, and hammer (Compl. ¶10). The complaint alleges the device includes a trigger with a trough housing the disconnector, a trigger sear hook with an aperture, and various contact surfaces and engagement means that work together to create a two-stage pull and release the hammer (Compl. ¶¶12, 14, 15, 16). The product is marketed for use in firearms like AR-15 type rifles (Compl. ¶7). No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

’338 Patent Infringement Allegations

Claim Element (from Independent Claim 7)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
a. a spring loaded trigger, a spring loaded disconnector and a spring loaded hammer;	The Accused Device is comprised of a spring loaded trigger, a spring loaded disconnector and a spring loaded hammer.	¶10	col. 4:48-52
c. said trigger having a trough which houses said disconnector and having a trigger sear hook located near the front of said trigger which incorporates the primary trigger sear and an aperture through said trigger sear hook for said disconnector to operate, said aperture comprises an opening of sufficient size to allow the disconnector to fully traverse the length of the trigger sear hook aperture and exit the front side of the trigger sear hook;	The trigger on the Accused Device has a trough which houses said disconnector and has a trigger sear hook with an aperture through it that allows the disconnector to fully traverse its length and exit the front side.	¶12	col. 4:60-67
d. the hammer being pivotally connected to the firearm;	The Accused Device includes a hammer that is pivotally connected to the firearm.	¶13	col. 4:45-47
e. said trigger having a pulling surface for the shooter to pull said trigger and said trigger and said hammer each including an engagement means for engaging each other so that said hammer is held in a cocked position prior to said trigger being actuated;	The trigger has a pulling surface, and the trigger and hammer each include an engagement means for engaging each other to hold the hammer in a cocked position before actuation.	¶14	col. 5:6-9
f. said disconnector being pivotally connected to the trigger, said disconnector having a contact means for interacting with the hammer to increase the pressure required to pull the trigger and having a disconnector spring for holding said disconnector in a predetermined position...	The disconnector is pivotally connected to the trigger, has a contact means for interacting with the hammer to increase the required trigger pull pressure, and has a disconnector spring for holding it in a predetermined position.	¶15	col. 5:10-17
g. said hammer further including a contact means for contacting said disconnector contact means so that when said trigger is first pulled the contact means contacts said disconnector and increases the pressure required to pull said trigger completely and disengage the engagement means of said hammer and said trigger.	The hammer includes a contact means that contacts the disconnector's contact means when the trigger is pulled, increasing the pressure required to fully pull the trigger and disengage the hammer.	¶16	col. 5:42-53

Identified Points of Contention

• Scope Questions: A central question may be whether the term "aperture through said trigger sear hook," as claimed, requires the specific geometry and function of allowing the disconnector to "exit the front side of the trigger sear hook." The analysis will depend on how the accused device's components are arranged and operate relative to the structure disclosed in the patent (e.g., aperture 42 shown in Fig. 2).
• Technical Questions: The complaint alleges infringement of several "means-plus-function" limitations (e.g., "engagement means," "contact means"). For these elements, the court must first construe the claimed function and then determine whether the specific structure in the accused device that performs the function is the same as, or equivalent to, the corresponding structure described in the patent's specification. The complaint does not identify the specific structures in the accused device, which will be a key issue for discovery and expert testimony.

V. Key Claim Terms for Construction

• The Term: "contact means" (Claim 7(f) and 7(g))

• Context and Importance: This term appears in two limitations describing the interaction between the disconnector and the hammer that creates the "wall" of the second trigger stage. As a "means-plus-function" term under 35 U.S.C. § 112(f), its scope is not merely its dictionary definition but is limited to the specific structures disclosed in the specification for performing the recited function, and their equivalents. The infringement analysis for this critical feature hinges entirely on this construction.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The patent uses general functional language in the claim itself: "contact means for interacting with the hammer to increase the pressure required to pull the trigger" (col. 8:10-13) and "contact means for contacting said disconnector contact means" (col. 8:20-22). A party might argue this language covers any surfaces that achieve this function.
  • Evidence for a Narrower Interpretation: The specification discloses specific corresponding structures. For the disconnector's contact means, the structure is the "disconnector face 41" ('338 Patent, col. 5:43-44; Fig. 7). For the hammer's contact means, the structure is the "secondary hammer sear hook 23" ('338 Patent, col. 5:42-45; Fig. 7). A party will argue that the claim is limited to these specific structures and their equivalents, and that any accused device lacking these specific interacting hooks does not infringe.

• The Term: "aperture through said trigger sear hook" (Claim 7(c))

• Context and Importance: Practitioners may focus on this term because it defines a key structural relationship between the trigger and disconnector. The claim requires the aperture to be "of sufficient size to allow the disconnector to fully traverse the length of the trigger sear hook aperture and exit the front side of the trigger sear hook." (col. 7:64-67). This functional requirement suggests the term is not just any hole, but one with a specific purpose and capability that may not be present in all trigger designs.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The term "aperture" is generally broad. A party could argue any opening that allows the disconnector to pass through the trigger body in the vicinity of the sear hook meets this limitation.
  • Evidence for a Narrower Interpretation: The specification explicitly shows "aperture 42" which allows the disconnector to pass "through and under the trigger sear hook 21" ('338 Patent, col. 4:63-66). The language "exit the front side" in the claim may be interpreted to require a specific path of travel relative to the trigger body, potentially narrowing the scope to designs that closely mirror Figure 2.

VI. Other Allegations

• Indirect Infringement: The complaint does not plead specific facts to support claims for either induced or contributory infringement. The allegations are focused on direct infringement through the making, using, and selling of the Accused Device (Compl. ¶8).
• Willful Infringement: The complaint alleges that the Defendant has had knowledge of the ’338 Patent "since at least December 17, 2018, as reflected in the cease and desist letter" and that any subsequent infringement is "knowing and willful." (Compl. ¶20). This allegation of pre-suit notice forms the basis for seeking enhanced damages.

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

The resolution of this dispute will likely depend on the court's determination of the following key questions:

1. A central issue will be one of claim construction under § 112(f): What are the specific structures disclosed in the ’338 Patent that correspond to the claimed "contact means" function, and does the Defendant's Two-Stage Trigger Group utilize the same or equivalent structures to create its second-stage trigger pull?
2. A second issue will be one of structural and functional equivalence: Does the accused trigger’s design, particularly the relationship between its disconnector and trigger body, incorporate an "aperture through said trigger sear hook" that performs the claimed function of allowing the disconnector to "exit the front side," or is there a fundamental difference in the mechanical arrangement and operation?
3. An evidentiary question will be one of timing and knowledge: Assuming infringement is found, can the Plaintiffs prove the Defendant received the December 17, 2018 cease and desist letter, thereby establishing the post-notice knowledge required to support a finding of willful infringement?