DCT
2:22-cv-14174
Surface Preparation Tech LLC v. Waterblasting LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Surface Preparation Technologies, LLC (Pennsylvania)
- Defendant: Waterblasting, LLC d/b/a Hog Technologies (Delaware)
- Plaintiff’s Counsel: Lott & Fischer, PL; Merchant Gould P.C.
- Case Identification: 2:22-cv-14174, S.D. Fla., 05/16/2022
- Venue Allegations: Venue is alleged to be proper as Defendant has committed acts of infringement and maintains a regular and established place of business in the Southern District of Florida.
- Core Dispute: Plaintiff alleges that Defendant’s road grinding and grooving machines infringe three patents related to systems for cutting rumble strips, including specialized sinusoidal grooves, and for controlling the cutting process.
- Technical Context: The technology concerns truck-mounted, computer-controlled equipment for cutting grooves into road surfaces to create safety features like rumble strips, which alert drivers through vibration and sound.
- Key Procedural History: The complaint alleges that Defendant had pre-suit knowledge of at least two of the patents-in-suit. Specifically, it alleges Plaintiff sent a cease and desist letter regarding the ’063 patent in December 2017 and that Defendant cited both the ’063 and ’310 patents in an Information Disclosure Statement (IDS) during its own patent prosecution in June 2018. The complaint also notes a cease and desist letter regarding all three patents was sent in March 2022. These allegations may be significant for the claim of willful infringement.
Case Timeline
| Date | Event |
|---|---|
| 2011-12-01 | U.S. Patent 8,821,063 Priority Date |
| 2012-05-25 | U.S. Patent 9,121,148 Priority Date |
| 2013-09-20 | U.S. Patent 9,574,310 Priority Date |
| 2014-09-02 | U.S. Patent 8821063 Issued |
| 2015-09-01 | U.S. Patent 9121148 Issued |
| 2017-02-21 | U.S. Patent 9574310 Issued |
| 2017-12-15 | Plaintiff sends cease and desist letter to Defendant regarding '063 Patent |
| 2018-06-08 | Defendant cites '063 and '310 Patents in an Information Disclosure Statement |
| 2022-03-15 | Plaintiff sends cease and desist letter to Defendant regarding all three patents-in-suit |
| 2022-05-16 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,574,310 - METHOD AND APPARATUS FOR CUTTING A SINUSOIDAL GROOVE IN A ROAD SURFACE
The Invention Explained
- Problem Addressed: The patent's background describes that while traditional rumble strips are effective safety features, the external noise they generate can be a significant disturbance to nearby homes and businesses (’310 Patent, col. 1:32-40). Prior solutions, such as adhering pre-formed sinusoidal rails to the road, were prone to detachment and damage from traffic and snowplows (Compl. ¶11).
- The Patented Solution: The invention is a system that cuts a continuous, durable sinusoidal groove directly into the road surface. It uses a controller to precisely adjust a rotatable cutting head, keeping it in "continuous engagement" with the road to create a subsurface strip with a variable, sinusoidal depth profile (’310 Patent, Abstract; col. 12:4-10). This creates a rumble strip that generates alerting noise inside a vehicle while minimizing external noise disturbances (Compl. ¶10).
- Technical Importance: This technology offered a method to create more durable and reliable noise-reducing sinusoidal rumble strips compared to the less permanent surface-adhered rails used previously (Compl. ¶11).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶16, 45, 47).
- Essential elements of claim 1 include:
- A rotatable cutting head.
- A cylinder connected to the cutting head for driving it into contact with the road surface.
- A controller that controls the cylinder to adjust the cutting head in continuous engagement with the road surface.
- The controller is configured to cut a subsurface sinusoidal strip.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 8,821,063 - CONTROL SYSTEM AND METHOD FOR ROAD CUTTING MACHINE
The Invention Explained
- Problem Addressed: The patent identifies an inefficiency in prior art road cutting machines where operators had to stop the machine to manually reprogram control parameters when the forward speed of the cutting vehicle changed, leading to production delays (’063 Patent, col. 2:37-47).
- The Patented Solution: The invention provides a control system that automatically and continuously adjusts the cutting operation in proportion to the machine's forward speed. The controller is programmed with an input/output function that varies a "proportional gain" and an "error amplification signal" based on the machine's speed, using linear interpolation between predefined speed points to make adjustments on the fly (’063 Patent, Abstract; Fig. 6). This allows the machine to maintain cutting consistency without interrupting production to reprogram for speed changes.
- Technical Importance: This adaptive control system improved the efficiency of rumble strip creation by allowing for continuous operation across a range of vehicle speeds without requiring manual intervention.
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶19, 69, 71).
- Essential elements of claim 1 include:
- A system comprising a rotatable cutting head, a cylinder, and a controller.
- The controller is programmed to vary a "proportional gain" and an "error amplification signal" over a range of forward speed of the cutting machine.
- The varying proportional gain increases and decreases the speed of the cutting head proportionally with the forward speed of the cutting machine.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 9,121,148 - METHOD AND APPARATUS FOR CUTTING GROOVES IN A ROAD SURFACE
Technology Synopsis
This patent addresses the challenge of maintaining a precise, consistent groove depth during road cutting. It discloses a system using one or more distance sensors (e.g., lasers) to provide real-time feedback to a controller. By comparing sensor readings of the uncut road surface with readings from the bottom of the freshly cut groove, the system can continuously adjust the cutting head's position to compensate for surface irregularities and maintain the desired depth (’148 Patent, Abstract; col. 2:8-20).
Asserted Claims
The complaint asserts independent claim 13 (Compl. ¶22).
Accused Features
The infringement allegation targets the "smart cylinders" and "computer-controlled precision depth control" features of the Grinder Hog and Rumble Hog products, which are alleged to use sensors to control cutting depth (Compl. ¶92.a, 95.a).
III. The Accused Instrumentality
Product Identification
The Grinder Hog and Rumble Hog, which are truck-mounted road surface cutting machines (Compl. ¶25).
Functionality and Market Context
The accused products are used to grind pavement, cut grooves for markings, and create rumble strips (Compl. ¶27, 34). The complaint identifies several key technical features: a rotatable cutting head (side-mounted on the Grinder Hog, rear-mounted on the Rumble Hog), "Hydraulic Smart cylinders" or "Skip Cylinders" that raise and lower the cutter, and a programmable digital controller (PLC) (Compl. ¶35, 45, 47; Exhibit G at 36). A screenshot from product marketing depicts the user interface for programming "Sinusoidal Cutting" on the Grinder Hog (Compl. p.13). The products are marketed with features such as "Computer-Controlled Profiling (CCP)" and "precision depth control" (Compl. ¶92.a).
The complaint alleges that Defendant and its customers use the Grinder Hog and Rumble Hog to compete directly with Plaintiff for road construction projects (Compl. ¶26).
IV. Analysis of Infringement Allegations
U.S. Patent No. 9,574,310 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a rotatable cutting head; | The accused Grinder Hog and Rumble Hog products are equipped with rotating grinder/cutter heads for cutting road surfaces. | ¶45.a, ¶47.a | col. 3:1-9 |
| a cylinder connected to the rotatable cutting head for driving the rotatable cutting head into contact with the road surface; | The products include "Hydraulic Smart cylinders" or "Skip Cylinders" which are connected to and control the vertical position of the cutting head. | ¶45.b, ¶47.b | col. 4:31-41 |
| and a controller; wherein the controller controls the cylinder to adjust the cutting head in continuous engagement with the road surface and to cut a subsurface sinusoidal strip... | The products feature a digital controller with a specific "Sinusoidal Cutting" mode, which allegedly controls the cylinders to continuously adjust the cutting head to form a sinusoidal groove. A screenshot of the controller's user interface is provided as evidence of this capability. | ¶45.c, ¶47.c | col. 12:4-10 |
U.S. Patent No. 8,821,063 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A system for controlling a cutting machine ... comprising a rotatable cutting head, a cylinder ... and a controller; | The accused products are road cutting systems that include a cutting head, hydraulic cylinders, and a digital controller. | ¶69.a, ¶69.b, ¶71.a, ¶71.b | col. 2:1-4 |
| wherein the improvement comprises: the controller programmed to vary a proportional gain and an error amplification signal over a range of forward speed of the cutting machine, | The controller includes a "Profile Speed Control" feature that allows the operator to set the cutting speed as a percentage of the truck's forward speed. This is alleged to be a method of varying a proportional gain signal based on the machine's speed. | ¶69.c, ¶71.c | col. 6:28-32 |
| wherein the varying proportional gain increases and decreases the speed of the cutting head proportionally with the forward speed of cutting machine. | The "Profile Speed Control" functionality is alleged to make the speed of the cutting head directly proportional to the forward speed of the truck, as the cutting speed is a set percentage of the fluctuating truck speed. | ¶69.c, ¶71.c | col. 11:4-6 |
Identified Points of Contention
- Scope Questions: For the ’310 Patent, a central issue may be the interpretation of "continuous engagement." The court may need to decide if the accused system's method of adjusting the cutter head to approximate a sine wave meets this requirement, or if the term implies a stricter, uninterrupted contact with the road surface throughout the adjustment cycle.
- Technical Questions: For the ’063 Patent, a key dispute may arise over whether the accused "Profile Speed Control" function, which adjusts cutting speed as a percentage of vehicle speed, performs the function of varying a "proportional gain and error amplification signal" as required by the claim. The analysis will likely focus on whether the defendant's control logic is technically equivalent to the specific control method described in the patent.
V. Key Claim Terms for Construction
Term: "continuous engagement" (’310 Patent, Claim 1)
- Context and Importance: The infringement reading of the '310 patent hinges on this term. Practitioners may focus on this term because the defendant could argue its system creates a sinusoidal profile through a series of discrete, rapid adjustments, which may not constitute "continuous" engagement if the term is narrowly construed.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent's objective is to create a "continuous sinusoidal strip" (’310 Patent, Abstract). This focus on the continuous nature of the result could support an interpretation that allows for minor, incidental breaks in contact so long as a continuous groove is formed.
- Evidence for a Narrower Interpretation: The claim language recites that the controller "controls the cylinder to adjust the cutting head in continuous engagement" (’310 Patent, col. 12:4-6). This phrasing focuses on the action itself, which could support a stricter definition requiring uninterrupted physical contact between the cutter and the road surface during the entire cutting and adjustment process.
Term: "proportional gain" (’063 Patent, Claim 1)
- Context and Importance: This is a technical term of art in control systems engineering. The infringement analysis for the '063 patent will depend heavily on whether the accused "Profile Speed Control" feature falls within the technical scope of this term.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent describes the system functionally as one that automatically adjusts to speed changes using a six-point input/output profile to avoid stopping the machine (’063 Patent, col. 6:46-55). This functional description could support construing "proportional gain" broadly to cover any control logic, like the accused percentage-based speed setting, that achieves this proportional speed adjustment.
- Evidence for a Narrower Interpretation: The specification provides a detailed discussion of "P-Gain" variables and the ability to tune them, and Figure 6 explicitly labels the y-axis of its control profile as "Proportional Gain" (’063 Patent, col. 7:6-10; Fig. 6). This could support a narrower construction limited to specific types of gain parameters used in formal control loop theory, which the defendant may argue its system does not use.
VI. Other Allegations
Indirect Infringement
The complaint alleges both induced and contributory infringement for all three patents. The allegations are based on Defendant's marketing materials, product manuals, and website advertisements, which allegedly instruct and encourage customers to use the accused Grinder Hog and Rumble Hog products in an infringing manner, such as by using the "Sinusoidal Cutting" or "Profile Speed Control" features (Compl. ¶54, ¶78, ¶102).
Willful Infringement
The complaint alleges willful infringement based on both pre-suit and post-suit knowledge. The central allegation for pre-suit knowledge is that Defendant cited the ’310 and ’063 patents in an Information Disclosure Statement (IDS) filed during the prosecution of its own patent application on June 8, 2018 (Compl. ¶49, ¶73). It further alleges that a cease and desist letter regarding the '063 patent was sent as early as December 15, 2017 (Compl. ¶73). Knowledge for all patents is also alleged based on a March 15, 2022 cease and desist letter (Compl. ¶97).
VII. Analyst’s Conclusion: Key Questions for the Case
- A key evidentiary and legal question will be one of technical implementation: Does the accused "Profile Speed Control" feature, which sets cutting speed as a percentage of vehicle speed, meet the specific requirements of varying a "proportional gain and error amplification signal" as that language is construed from the '063 patent, or is there a fundamental mismatch in the underlying control logic?
- A core issue will be one of claim scope: can the term "continuous engagement," used in the '310 patent to describe the cutting of a sinusoidal groove, be construed to read on the operation of the accused machines, whose exact cutting mechanics will be a subject of discovery?
- A central dispute will concern knowledge and intent: Given the complaint’s allegation that the Defendant cited the Plaintiff’s patents during its own patent prosecution years before this lawsuit, the question of whether any infringement was willful is positioned to be a critical and fact-intensive part of the case, carrying significant implications for potential damages.