Slide Fire Solutions LP v. Bair Arms LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Slide Fire Solutions LP (Texas)
  • Defendant: Bair Arms LLC (Virginia)
  • Plaintiff’s Counsel: PATTERSON + SHERIDAN, LLP
• Case Identification: 3:17-cv-00999, N.D. Tex., 04/10/2017
• Venue Allegations: Plaintiff alleges venue is proper in the Northern District of Texas because Defendant solicits customers in Texas through its websites and because a substantial percentage of Defendant's allegedly infringing sales are made to Texas residents.
• Core Dispute: Plaintiff alleges that Defendant’s "Bump Fire Assistance Devices" infringe patents related to methods and devices for increasing the rate of fire of semi-automatic firearms.
• Technical Context: The technology involves accessories, commonly known as "bump stocks," that utilize a semi-automatic rifle's recoil energy to enable a rapid rate of fire mimicking automatic fire.
• Key Procedural History: The complaint alleges that Plaintiff first notified Defendant of infringement of the lead patent in August 2015, after which Defendant allegedly agreed to cease manufacture. The complaint further alleges that Defendant later resumed selling modified products. A third party initiated an ex parte reexamination of the lead patent, which concluded with the USPTO confirming the patentability of all original claims, a fact that may strengthen the patent's presumption of validity.

Case Timeline

Date	Event
2009-11-18	Priority Date for ’658 and ’836 Patents
2012-03-06	U.S. Patent 8,127,658 Issues
2015-08-18	Plaintiff sends first notice letter to Defendant regarding ’658 Patent
2015-09-10	Defendant agrees in writing to cease manufacture of accused product
2015-11-11	Ex parte reexamination of ’658 Patent requested by third party
2016-10-07	USPTO issues reexamination certificate for ’658 Patent
2017-01-17	U.S. Patent 9,546,836 Issues
2017-01-25	Plaintiff sends second notice letter to Defendant regarding ’658 Patent
2017-04-10	Complaint Filed

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

U.S. Patent 8,127,658 - "Method of Shooting a Semi-Automatic Firearm," issued March 6, 2012

The Invention Explained

• Problem Addressed: The patent describes prior art "bump firing" techniques as having significant safety and accuracy issues because the operator cannot maintain a firm grip on the firearm (’658 Patent, col. 2:44-52). Devices using springs to assist in bump firing are also described as potentially complex and dependent on the specific ammunition used (’658 Patent, col. 2:35-43).
• The Patented Solution: The invention is a method for rapidly firing a semi-automatic weapon that allows the user to maintain a stable hold. A handle or stock slideably supports the firearm's receiver and barrel, allowing them to move back and forth along a linear path (’658 Patent, col. 3:45-50). The user holds the handle stationary with one hand and uses their other hand to apply a constant forward force to the firearm. This forward force causes the firearm’s trigger to collide with the user's stationary trigger finger, which acts as a passive "actuator," firing a round. The firearm's recoil then pushes it rearward, separating it from the trigger finger and allowing the trigger to reset, after which the user's continuous forward pressure immediately repeats the cycle (’658 Patent, col. 10:29-54).
• Technical Importance: The claimed method purports to increase the rate of fire of a semi-automatic firearm without compromising the safety and accuracy that a stable, two-handed grip provides (’658 Patent, col. 3:51-59).

Key Claims at a Glance

• The complaint asserts independent claims 1 and 13 (Compl. ¶19).
• Independent Claim 1 recites a method of firing a semi-automatic firearm with steps that include:
  • Slideably supporting a "firing unit" (receiver, barrel, trigger) in a handle for linear reciprocating movement.
  • Stabilizing an "actuator" (e.g., a finger) in a stationary position relative to a user's second body part (e.g., the hand gripping the handle).
  • Using human muscle power from a first body part (e.g., the other hand) to generate a "forward activation force" that urges the firing unit forward, causing the trigger to collide with the actuator.
  • Discharging a round, which generates a recoil force that translates the firing unit rearwardly.
  • Repeating the forward movement to cause a second collision and subsequent firing.
• Independent Claim 13 recites a similar method, adding the limitation that the rearward recoil separates the trigger from the actuator by "at least a predetermined distance (D)."
• The complaint reserves the right to assert other claims, including dependent claims 2-3 and 14-15 (Compl. ¶19).

U.S. Patent 9,546,836 - "Slide Stock for Firearm with Retractable Lock Pin," issued January 17, 2017

The Invention Explained

• Problem Addressed: The patent identifies the same problems as its parent ’658 patent: the lack of safety and accuracy in conventional bump-firing techniques (’836 Patent, col. 1:40-54).
• The Patented Solution: This patent claims an apparatus—a physical "sliding bump stock"—rather than a method. The stock includes a handle, a forward-extending finger rest to stabilize the user's non-moving trigger finger, and a surface that interacts with a bearing element on the firearm to allow for the requisite sliding motion (’836 Patent, col. 4:1-10). Critically, the invention includes a "lock" (such as a retractable pin) that allows the user to selectively disable the sliding function, thereby arresting the reciprocating movement and allowing the firearm to be used in a standard, single-shot semi-automatic mode (’836 Patent, col. 4:10-15).
• Technical Importance: The invention provides a single device that enables both a rapid-fire mode and conventional semi-automatic operation, offering enhanced versatility and user control (’836 Patent, col. 4:26-30).

Key Claims at a Glance

• The complaint asserts independent claims 1 and 11 (Compl. ¶29).
• Independent Claim 1 recites a "sliding bump stock" apparatus comprising:
  • A handle with a forward-extending finger rest configured to stabilize a user's trigger finger.
  • An opposing surface for interacting with a bearing element on the firearm, enabling reciprocation along a constrained linear path.
  • A movable lock for "selectively stopping reciprocating movement" of the handle relative to the firearm trigger.
• Independent Claim 11 recites a "sliding bump stock and interface system assembly," which includes the handle and lock from Claim 1 plus a "bearing element" adapted for attachment to the firearm.
• The complaint reserves the right to assert other claims, including dependent claims 2-3, 16, and 19 (Compl. ¶29).

III. The Accused Instrumentality

Product Identification

The complaint identifies "a series of slide-action Bump Fire Assistance Devices" for various rifle platforms, which are referred to collectively as "Bump Fire products" (Compl. ¶3). Specific product names mentioned include "AK Bump Grip," "AK GEN2 BUMP FIRE," and "Gen2AK" (Compl. ¶¶12, 14).

Functionality and Market Context

The accused products are described as gun stocks that incorporate a "linear slide-action" feature (Compl. ¶¶1, 9, 12). The complaint specifically alleges that since January 2017, Defendant has modified its products to include a "retractable lock pin feature" (Compl. ¶14). The products are allegedly sold online and at gun shows for a variety of popular rifle platforms, with the complaint noting that models for additional platforms are "coming soon" (Compl. ¶3, ¶12, ¶14).

IV. Analysis of Infringement Allegations

The complaint references preliminary infringement claim charts attached as Exhibits A and B but does not include these exhibits in the filing (Compl. ¶19, ¶29). As such, this analysis is based on the narrative allegations. No probative visual evidence provided in complaint.

The complaint alleges that by making, using, and selling the Bump Fire products, Defendant directly infringes, induces others to infringe, and contributorily infringes the asserted patents (Compl. ¶18, ¶28). The core of the infringement theory for the ’658 Patent appears to be that the "linear slide-action" of the accused products enables users to perform the patented method of firing. For the ’836 Patent, the infringement allegation appears to map the accused product's "retractable lock pin feature" directly onto the "lock" element recited in the apparatus claims (Compl. ¶14).

V. Key Claim Terms for Construction

• Term: "stabilizing an actuator in a stationary position" (’658 Patent, Claim 1)

  • Context and Importance: This phrase is central to the patented method, as it defines the passive role of the user's trigger finger. The dispute will likely focus on whether the term requires a specific physical structure (like the finger rest shown in the patent) or can be met by any user technique enabled by the accused product. Practitioners may focus on this term because it distinguishes the invention from methods involving an active trigger pull.
  • Intrinsic Evidence for a Broader Interpretation: The specification defines "actuator" to include "a finger or other stationary object," which could support an interpretation not limited to a human finger (’658 Patent, col. 8:2-3).
  • Intrinsic Evidence for a Narrower Interpretation: The embodiments consistently depict the actuator as an index finger placed on a dedicated "finger rest" (70) that is part of the handle (’658 Patent, Fig. 10; col. 7:65-col. 8:1). A defendant may argue this context limits the scope of "stabilizing."

• Term: "a lock movable... for selectively stopping reciprocating movement" (’836 Patent, Claim 1)

  • Context and Importance: This functional language is the key feature of the patented apparatus. The infringement analysis for the ’836 Patent will turn on whether the accused product's "retractable lock pin feature" (Compl. ¶14) is structurally and functionally equivalent to this limitation.
  • Intrinsic Evidence for a Broader Interpretation: Plaintiff may argue that the claim term is written in broad functional language and should cover any mechanism that performs the stated function of selectively stopping the sliding motion.
  • Intrinsic Evidence for a Narrower Interpretation: The specification discloses a specific embodiment of the lock: a rotatable cam (46) that drives a pin (48) into a detent (51) on the firearm's buffer tube (’836 Patent, col. 6:14-51; Fig. 10). A defendant may argue that the claim should be construed to be limited to this structure or its equivalents.

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement for both patents. It asserts that Defendant had knowledge of the patents based on notice letters sent in August 2015 and January 2017 (Compl. ¶10, ¶13). It further alleges the accused products are "especially made or especially adapted" for infringement and are not staple articles of commerce with substantial non-infringing uses (Compl. ¶18, ¶28).
• Willful Infringement: Willfulness is alleged for both patents. The allegations are based on Defendant’s continued sales after receiving actual notice of the patents, particularly the alleged resumption of sales after an initial agreement to cease manufacturing and the subsequent modification of the products to include features allegedly covered by the more recent ’836 Patent (Compl. ¶11, ¶13-14, ¶22, ¶32).

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

1. A key evidentiary question will be one of technical mapping: In the absence of the complaint's claim chart exhibits, what specific evidence will Plaintiff offer to demonstrate that the accused "Bump Fire products," particularly the alleged "retractable lock pin feature," perform the exact functions and possess the structures required by the asserted claims of the ’658 and ’836 patents?
2. The case will likely involve a central dispute over claim scope: For the ’836 patent, can the functional term "lock... for selectively stopping reciprocating movement," which is disclosed as a specific cam-and-pin mechanism, be construed to cover the particular locking mechanism used in the accused products?
3. A significant factual issue will be one of intent: Did Defendant's alleged conduct—specifically, continuing to sell products after receiving multiple notice letters and after an ex parte reexamination confirmed the validity of the ’658 patent’s claims—constitute willful infringement justifying enhanced damages?