GD Energy Products LLC v. Kerr Machine Co

Prosecution History analysis

Examiner Search analysis

Invalidity Framework analysis

Petition

Petition summary

## 1. Case Identification
- Case Number: [PGR2025-00031](https://ai-lab.exparte.com/case/ptab/PGR2025-00031)
- Patent #: [12,152,582](https://ai-lab.exparte.com/patent/12152582)
- Filed: February 6, 2025
- Petitioner(s): [GD Energy Products, LLC](https://ai-lab.exparte.com/party/gd-energy-products-llc)
- Patent Owner(s): [Kerr Machine Company](https://ai-lab.exparte.com/party/kerr-machine-co)
- Challenged Claims: 1-15

## 2. Patent Overview
- Title: Fluid End Assembly
- Brief Description: The ’582 patent is directed to a fluid end assembly for a multiplex reciprocating pump. The purported novelty is a design that seals fluid flow bores using a large plate fastened to the housing's exterior to cover multiple adjacent bore openings, thereby eliminating the need for conventional retaining nuts threaded into the walls of each individual bore.

## 3. Grounds for Unpatentability

#### Ground 1: Claims 1-14 are obvious over Kerr
- **Prior Art Relied Upon:** [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) KP-3300HP Plunger Pump Service Manual (“[Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004)”).
- **Core Argument for this Ground:**
  - **Prior Art Mapping:** Petitioner asserted that the [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) manual, which describes a conventional triplex plunger pump, explicitly illustrates every element of claims 1-14. [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) discloses a fluid end assembly with a monoblock housing, multiple horizontal and vertical bores forming internal chambers, and plunger assemblies. Critically, Petitioner argued that [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) teaches the core claimed feature: a single cover plate fastened to the housing that covers multiple horizontal bores. The claim limitations reciting a "second" plunger arrangement (e.g., second bore, second pair of valves) were argued to be obvious because [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) is a triplex pump, and a person of ordinary skill in the art (POSITA) would understand that each of the three plunger assemblies is homologous and possesses the same structure.
  - **Key Aspects:** This ground contends the patented invention is nothing more than a conventional pump design that was already described in the Patent Owner's own service manual. Petitioner also provided extensive evidence to establish the [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) manual as a prior art printed publication available before the patent's priority date.

#### Ground 2: Claims 1-14 are obvious over Aplex in view of Stanton
- **Prior Art Relied Upon:** Dupagro Aplex SC65 Manual (“[Aplex](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1005)”), U.S. Pre-Grant Publication No. 2005/0200081 (“[Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007)”).
- **Core Argument for this Ground:**
  - **Prior Art Mapping:** Petitioner argued that [Aplex](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1005), a manual for another conventional triplex pump, discloses the fundamental fluid end assembly, including the housing, multiple side-by-side bores, and the use of a single plate to cover the horizontal bores. However, [Aplex](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1005) teaches a stuffing box that is bolted to the exterior of the fluid end. [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007) was introduced because it discloses an alternative, well-known stuffing box arrangement where the "component" (a packing sleeve) is installed at least partially *within* the horizontal bore of the fluid end housing.
  - **Motivation to Combine:** A POSITA would combine these references by replacing the external packing assembly of [Aplex](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1005) with the internal packing assembly of [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007). Petitioner argued this would be a simple substitution of one known method of providing packing for another to achieve predictable results. The motivation would be to gain the known benefits of Stanton’s design, such as improved pressure/fluid isolation and a more integrated assembly.
  - **Expectation of Success:** A POSITA would have a high expectation of success, as the modification involves the routine substitution of one interchangeable, commercially-known component (a packing assembly) for another in a standard pump design.

#### Ground 3: Claims 1-14 are obvious over Blume in view of Stanton and Wilkinson
- **Prior Art Relied Upon:** U.S. Patent No. 7,186,097 (“[Blume](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1006)”), [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007), U.S. Patent No. 4,773,833 (“[Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008)”).
- **Core Argument for this Ground:**
  - **Prior Art Mapping:** Petitioner asserted that [Blume](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1006) discloses a conventional triplex pump fluid end with most of the claimed structural features, but it uses individual threaded retainers to cover its bores rather than a single plate. The combination with [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007) provides the claimed internal stuffing box/packing sleeve arrangement for the same reasons articulated in Ground 2. The combination with [Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008) provides the final key element: the use of a bolted-on plate to cover multiple bores. [Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008) explicitly teaches accessing valves "by removal of a plate 44" that covers a set of three bores.
  - **Motivation to Combine:** A POSITA would combine [Blume](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1006) with [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007) for improved packing performance. A POSITA would also be motivated to replace the individual threaded bore covers of [Blume](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1006) with the single plate cover taught by [Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008). Petitioner argued this is a simple design choice, substituting one known bore closure method for another to simplify manufacturing and maintenance, which are well-known engineering goals.
  - **Expectation of Success:** Success would be expected because the combination merely integrates known features (a pump from [Blume](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1006), a packing assembly from [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007), a cover plate from [Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008)) for their intended and well-understood functions.

- **Additional Grounds:** Petitioner asserted an additional obviousness challenge (Ground 4) based on the public offer for sale of the [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004) Pump, which relies on the same technical disclosures as Ground 1. Petitioner also challenged claim 15 as indefinite under 35 U.S.C. §112 for lacking antecedent basis for "plurality of fasteners" and for being unclear how fasteners for the plate could also attach the retainer (Ground 5).

## 4. Arguments Regarding Discretionary Denial
- Petitioner argued that discretionary denial under §314(a) (considering *Fintiv* factors) is inappropriate because there are no co-pending proceedings related to the ’582 patent.
- Petitioner also argued against denial under §325(d), asserting that the art and arguments presented are not the same or substantially the same as those considered during prosecution. Specifically, the [Kerr](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1004), [Aplex](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1005), [Stanton](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1007), and [Blume](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1006) references were not before the examiner. While [Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008) was cited, it was in a different context. Petitioner contended the examiner erred by allowing the claims based on a misinterpretation that the claimed "plate" required openings not present in [Wilkinson](https://ai-lab.exparte.com/case/ptab/PGR2025-00031/doc/1008), a limitation that was, in fact, absent from the allowed claims.

## 5. Relief Requested
- Petitioner requests institution of an inter partes review and cancellation of claims 1-15 of Patent [12,152,582](https://ai-lab.exparte.com/patent/12152582) as unpatentable.

Reciprocating pump patent challenged: owner's own manual cited as prior art for obviousness of claims 1-15 based on its single cover plate design.