Pave/Lock/Plus II v. Smith: Concrete Block Patent Dispute Settles After 4+ Years
Pave/Lock/Plus II, LLC brought a patent infringement action against Lee A. Smith in the Southern District of Texas over articulated concrete block systems and erosion control products covered by US5556228A and US8123435B1. The case closed by settlement after 1,508 days — over four years of litigation in front of Judge Andrew S. Hanen.
A Four-Year Texas Patent Battle Over Concrete Block and Erosion Control IP
Pave/Lock/Plus II, LLC filed suit against Lee A. Smith in the U.S. District Court for the Southern District of Texas on October 16, 2020, asserting rights under two patents: US5556228A, covering articulated concrete block systems, and US8123435B1, directed to pavestones and concrete retaining walls used in erosion control applications. The case was assigned to Judge Andrew S. Hanen and carried a declaratory judgment cause of action, suggesting the dispute also involved questions about the validity or enforceability of the patents at issue.
The litigation concluded by settlement on December 2, 2024, with the court’s docket reflecting a ‘Case Settled’ basis of termination. Notably, the final docket activity involved an unopposed motion by defendant Pave/Lock/Plus II, LLC to unseal a prior court order (Docket No. 256), which the court granted — suggesting at least some substantive proceedings were conducted under seal before the parties resolved their dispute privately. The terms of any settlement, including licensing arrangements, damages, or ongoing obligations, remain confidential.
The 1,508-day duration — more than four years — is notably long even by patent litigation standards, suggesting the case involved substantive discovery, claim construction, and possibly motions practice before the parties reached agreement. The declaratory judgment framing is consistent with a scenario where validity or non-infringement was actively contested. What drove the ultimate settlement, and on what terms, cannot be determined from the public record; the sealing of Docket No. 256 further limits visibility into the case’s most consequential procedural developments.
Filing to Case Settled in 1508 days
1,508 days — well above the median U.S. patent case duration of roughly 700–900 days to resolution
Case settled: what the resolution means for both parties
Settlement ends litigation — no merits ruling issued
A ‘Case Settled’ termination means the parties reached a private agreement before any final judgment on infringement, validity, or damages. The court did not adjudicate the merits of the claims under US5556228A or US8123435B1. Neither patent has been judicially invalidated or found infringed as a result of this proceeding, leaving both patents technically enforceable unless challenged elsewhere.
No merits adjudicationPatents survive — enforceability intact absent further challenge
For Pave/Lock/Plus II, settlement preserves both asserted patents without the risk of an adverse invalidity or non-infringement ruling. The patents remain available for future enforcement or licensing. Settlement after extended litigation may also reflect negotiated commercial terms — such as a licensing arrangement — that the plaintiff found preferable to continued uncertainty at trial. The confidential nature of the resolution prevents any public signal about relative leverage.
Patents remain enforceableSmith avoids trial — but settlement terms are undisclosed
Settlement for Lee A. Smith ends the litigation without a public finding of infringement or liability. Whether Smith secured a license, paid consideration, agreed to design changes, or obtained a covenant not to sue cannot be determined from the public record. The unsealing motion at case close suggests at least one substantive order was previously sealed, which may indicate the parties managed sensitive terms carefully throughout the proceeding.
Terms confidentialConcrete block and erosion control IP remains an active enforcement zone
The willingness to litigate for over four years signals that Pave/Lock/Plus II treats US5556228A and US8123435B1 as commercially significant assets worth defending. Competitors and product developers in articulated concrete block systems, retaining walls, and erosion control should treat these patents as live enforcement risks. A settlement without a public invalidity ruling raises the bar for third parties seeking to design around or challenge these patents without incurring their own litigation costs.
Continued enforcement riskFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Pave/Lock/Plus II, LLC | Company | Concrete block system IP licensing entity — holder of US5556228A and US8123435B1Search in Eureka ↗ |
| Defendant | Lee A. Smith | Individual | Lee A. Smith — individual defendant in articulated concrete block patent disputeSearch in Eureka ↗ |
| Co-Defendant | Lee A. Smith | Individual | Search in Eureka ↗ |
| Plaintiff counsel | John Allen Yates | Attorney | Counsel for Pave/Lock/Plus II, LLCSearch in Eureka ↗ |
| Plaintiff law firm | Patterson Sheridan LLP | Law Firm | Representing Pave/Lock/Plus II, LLCSearch in Eureka ↗ |
| Defendant counsel | Robert N Hancock | Attorney | Counsel for Lee A. SmithSearch in Eureka ↗ |
| Defendant counsel | Steven N. Williams | Attorney | Counsel for Lee A. SmithSearch in Eureka ↗ |
| Defendant counsel | Winston Oliver Huff | Attorney | Counsel for Lee A. SmithSearch in Eureka ↗ |
| Defendant law firm | Munsch, Hardt, Kopf & Harr PC | Law Firm | Representing Lee A. SmithSearch in Eureka ↗ |
| Presiding judge | Judge Andrew S Hanen | Judge | Texas Southern District CourtSearch in Eureka ↗ |
Official order — verbatim text
The recorded verdict reflects a narrow procedural act: the court granted an unopposed motion to unseal Docket No. 256 at case close. This is not a substantive ruling on infringement or validity. The unsealing direction indicates that at least one significant order was shielded from public access during the litigation — its contents may now inform future claim construction or validity arguments involving US5556228A or US8123435B1. The declaratory judgment cause of action framing suggests the core dispute involved patent scope or validity, neither of which was resolved on the merits.
US5556228A & US8123435B1 — Articulated Concrete Block and Erosion Control Systems
US5556228A, filed under application number US08/383825, covers articulated concrete block systems — interlocking or linked block assemblies used primarily for erosion control in civil and environmental engineering applications such as channel linings, slope protection, and scour prevention. US8123435B1, filed under application US12/322450, is directed to pavestones and concrete retaining wall systems, extending protection into hardscape and structural retaining applications. Together, the two patents span a range of concrete masonry products with overlapping utility in erosion management and site stabilisation.
These patents occupy a commercially active niche at the intersection of civil engineering, environmental compliance, and hardscape construction. US5556228A, as an earlier-generation patent, may carry broader claims reflecting less crowded prior art at time of filing — making it a potentially powerful enforcement tool. US8123435B1’s more recent filing provides more targeted protection on specific product configurations. For manufacturers, distributors, or contractors involved in articulated block revetment, retaining wall systems, or permeable paving, both patents represent genuine freedom-to-operate risk, particularly given that the patent holder pursued active litigation for over four years.
Should you run an FTO against US5556228A and US8123435B1?
Any company designing, manufacturing, importing, or distributing articulated concrete block systems, erosion control revetment, pavestones, or concrete retaining wall products in the United States should assess its exposure to US5556228A and US8123435B1. The four-year litigation history of this case signals an active enforcement posture by Pave/Lock/Plus II. A settlement without invalidity ruling means neither patent has been publicly weakened — and both remain available for future enforcement against new targets.
PatSnap Eureka’s FTO Search Agent enables R&D and IP teams to map product features against the claim scope of both patents, identify prior art that may support invalidity arguments, and benchmark your product design against the prosecution history. Eureka can also surface related family members, continuation applications, and related enforcement activity — giving you a complete picture of the risk landscape before market entry or product launch in the concrete block and erosion control sector.
Run a freedom-to-operate analysis on US5556228A to assess your product’s exposure
Run FTO in Eureka →Similar Patent Cases: Concrete Block Systems & Erosion Control IP in U.S. District Courts
Related patent litigation involving articulated concrete block systems, erosion control technology, and retaining wall products heard in U.S. district courts — including the Southern District of Texas.
What this case signals for the erosion control and concrete block IP landscape
Four years of litigation culminating in a sealed-order settlement carries specific signals for IP holders and product developers in this niche but commercially active sector.
Long-duration settlement does not neutralise patent risk for third parties
The settlement of Pave/Lock/Plus II v. Smith leaves US5556228A and US8123435B1 with no adverse validity ruling on the public record. Any manufacturer or distributor of articulated concrete block systems, pavestones, or retaining wall products operating in the U.S. must treat these patents as enforceable. An FTO analysis against both patents is advisable before product launch or market entry.
Declaratory judgment framing signals contested validity — worth monitoring
The declaratory judgment cause of action in this case is consistent with Smith having challenged the validity or scope of the asserted patents. That challenge did not produce a public ruling, but it suggests the patents may have arguable weaknesses that were never tested to judgment. Parties considering invalidity challenges in a future proceeding should examine the prosecution history of US5556228A and US8123435B1 closely.
Pave/Lock/Plus v Lee — key questions answered
Two patents were asserted: US5556228A (articulated concrete block systems for erosion control, application US08/383825) and US8123435B1 (pavestones and concrete retaining wall systems, application US12/322450). The case also involved a declaratory judgment cause of action, suggesting validity or non-infringement was actively in dispute.
‘Case Settled’ means the parties reached a private agreement that terminated the litigation before any final merits judgment. No court ruling on patent infringement, validity, or damages was issued. The terms — including any licensing arrangement, payment, or injunctive relief — are confidential and not reflected in the public docket.
At case close, defendant Pave/Lock/Plus II filed an unopposed motion to unseal Docket No. 256, which the court granted. The prior sealing suggests a substantive order — potentially on claim construction, a dispositive motion, or a discovery matter — was shielded during litigation. The now-unsealed order may contain guidance relevant to the scope or validity of US5556228A or US8123435B1 in future proceedings.
The 1,508-day duration — over four years — is notably long and suggests the case involved substantial discovery, possibly claim construction proceedings, and contested motion practice before settlement. The declaratory judgment framing also typically involves validity challenges that add procedural complexity. The exact causes of delay are not fully apparent from the public docket, but the duration is consistent with heavily contested patent litigation.
Yes. Because the case settled without a merits ruling, neither US5556228A nor US8123435B1 was judicially invalidated or found unenforceable as a result of this litigation. Both patents remain on the public register and available for enforcement against third parties, unless separately challenged via inter partes review, ex parte reexamination, or future litigation.
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