Prior art — US Patent 11530654

To identify the most relevant prior art for US Patent 11530654, I have examined the "Citations" section of the patent document. For each reference cited by the examiner (indicated by an asterisk '*') and having a priority or publication date before US11530654's priority date of June 12, 2015, I've extracted the requested information. Given the extensive list of citations, I will provide a detailed analysis for the top ten most relevant prior art references, based on their titles' direct relevance to the inventive concepts of US11530654 (dual fuel systems, off-board two-stage fuel regulation, and mechanical lockout mechanisms).

Disclaimer: Determining definitive anticipation under 35 U.S.C. § 102 requires a detailed, claim-by-claim comparison and expert legal analysis, which is beyond the scope of this technical analysis. The "potential anticipation" discussed below highlights conceptual overlaps between the prior art and US11530654's claims.

Here is the analysis of the most relevant examiner-cited prior art for US Patent 11530654:

Most Relevant Prior Art for US11530654

1. US5320078A

Full Citation: US5320078A, "Remote mounting of a fuel pressure regulator for an engine" by Siemens Automotive L.P., published 1994-06-14.
Publication/Filing Date: Priority Date: 1992-03-11; Publication Date: 1994-06-14.
Brief Description: This patent describes a system for mounting a fuel pressure regulator remotely from an engine.
Potential Anticipation (35 U.S.C. § 102): This prior art directly addresses the "off board" or "remotely mounted" aspect of a fuel regulator system, as found in Claim 1, Claim 6, and Claim 10 of US11530654. It could potentially anticipate the broad concept of locating a fuel pressure regulator away from the engine. However, for full anticipation of Claims 1, 6, and 10, it would need to further disclose a two-stage regulation specifically for gaseous fuel supplied from a pressurized fuel source and the integration with a mechanical fuel lockout apparatus.

2. US6513476B1

Full Citation: US6513476B1, "Dual fuel system for internal combustion engine" by Generac Power Systems, Inc., published 2003-02-04.
Publication/Filing Date: Priority Date: 2001-03-23; Publication Date: 2003-02-04.
Brief Description: This patent discloses a dual fuel system designed for internal combustion engines.
Potential Anticipation (35 U.S.C. § 102): This document is highly relevant as it describes a "dual fuel system for internal combustion engines," directly overlapping with the core subject matter of US11530654, particularly Claims 1 and 6. It potentially anticipates the fundamental concept of operating an engine on both liquid and gaseous fuels and the selective control of fuel flow between them. A detailed comparison would be needed to determine if it teaches the specific "off-board two-stage fuel regulator system" and the unique "mechanical fuel lockout apparatus" that prevents physical coupling of a fuel source.

3. US6880509B2

Full Citation: US6880509B2, "Dual fuel system for internal combustion engine" by Generac Power Systems, Inc., published 2005-04-19.
Publication/Filing Date: Priority Date: 2001-03-23; Publication Date: 2005-04-19.
Brief Description: This patent also describes a dual fuel system for an internal combustion engine, likely an evolution or variation of the prior Generac patent.
Potential Anticipation (35 U.S.C. § 102): Similar to US6513476B1, this patent is highly relevant to Claims 1 and 6, which concern a dual fuel generator system. It potentially anticipates the broad concept of a dual fuel system for an IC engine. The specific features of the off-board two-stage gaseous fuel regulation and the mechanical fuel lockout apparatus of US11530654 would need to be present for full anticipation.

4. US6971358B2

Full Citation: US6971358B2, "Fuel pressure regulator" by Generac Power Systems, Inc., published 2005-12-06.
Publication/Filing Date: Priority Date: 2004-01-26; Publication Date: 2005-12-06.
Brief Description: This patent focuses on a fuel pressure regulator.
Potential Anticipation (35 U.S.C. § 102): This document potentially anticipates the component of a "fuel pressure regulator" as referenced in Claims 1, 6, and 10. For full anticipation of these claims, it would need to disclose a two-stage regulator, specifically for gaseous fuel from a pressurized source, and its "off-board" location, possibly in conjunction with a dual fuel system and lockout mechanism.

5. US7584742B2

Full Citation: US7584742B2, "Dual fuel control system for internal combustion engine" by Generac Power Systems, Inc., published 2009-09-08.
Publication/Filing Date: Priority Date: 2005-09-20; Publication Date: 2009-09-08.
Brief Description: This patent describes a control system specifically for dual fuel internal combustion engines.
Potential Anticipation (35 U.S.C. § 102): This patent directly addresses a "dual fuel control system" for an internal combustion engine, making it highly relevant to the control aspects of Claims 1 and 6. It potentially anticipates methods and apparatus for switching between different fuel sources. However, the specific implementation of an "off-board two-stage gaseous fuel regulator system" and the unique "mechanical fuel lockout apparatus" described in US11530654 would need to be present in this prior art for complete anticipation.

6. US7673595B2

Full Citation: US7673595B2, "Multi-fuel engine fuel delivery system with enhanced fuel cut-off valve" by Generac Power Systems, Inc., published 2010-03-09.
Publication/Filing Date: Priority Date: 2006-05-19; Publication Date: 2010-03-09.
Brief Description: This patent describes a fuel delivery system for multi-fuel engines, featuring an enhanced fuel cut-off valve.
Potential Anticipation (35 U.S.C. § 102): This document is highly relevant due to its focus on "multi-fuel engine fuel delivery systems" and an "enhanced fuel cut-off valve," which has functional similarities to the fuel control aspects and the mechanical lockout (specifically the liquid fuel cut-off) described in Claims 1 and 6 of US11530654. The novelty of US11530654 would lie in the specific "off-board two-stage gaseous fuel regulator system" and the distinct mechanical lockout mechanism that prevents the coupling of the second fuel source.

7. US8707925B2

Full Citation: US8707925B2, "Fuel flow control for dual fuel engine" by Kohler Co., published 2014-04-29.
Publication/Filing Date: Priority Date: 2012-02-15; Publication Date: 2014-04-29.
Brief Description: This patent focuses on controlling fuel flow in a dual fuel engine.
Potential Anticipation (35 U.S.C. § 102): As a "Fuel flow control for dual fuel engine," this patent potentially anticipates the broad concept of managing fuel flow for different fuel types in Claims 1 and 6. The specific combination of an "off-board two-stage gaseous fuel regulator system" and the distinctive "mechanical fuel lockout apparatus" of US11530654 would be key for differentiating.

8. US8985093B2

Full Citation: US8985093B2, "Dual fuel control apparatus" by Generac Power Systems, Inc., published 2015-03-24.
Publication/Filing Date: Priority Date: 2012-09-28; Publication Date: 2015-03-24.
Brief Description: This patent describes an apparatus for controlling dual fuel operation.
Potential Anticipation (35 U.S.C. § 102): This document, a "Dual fuel control apparatus," is highly relevant to the control and selection aspects of Claims 1 and 6. It potentially anticipates the general architecture for controlling two fuel sources. However, the specific design of the "off-board two-stage gaseous fuel regulator system" and the unique physical lockout mechanism of US11530654 would be areas of differentiation.

9. US20130146017A1

Full Citation: US20130146017A1, "Fuel control valve for a dual fuel engine" by Briggs & Stratton Corporation, published 2013-06-13.
Publication/Filing Date: Priority Date: 2011-12-07; Publication Date: 2013-06-13.
Brief Description: This patent application describes a fuel control valve specifically designed for a dual fuel engine.
Potential Anticipation (35 U.S.C. § 102): This patent application directly relates to the "mechanical fuel valve actuatable between a first position and a second position to selectively control fuel flow" and the "fuel lockout apparatus" described in Claims 1 and 6 of US11530654. It potentially anticipates the concept of using a valve to select between dual fuels. The unique feature of US11530654's lockout apparatus that prevents the second fuel source from coupling (i.e., physically blocking connection) would be a key point of comparison.

10. US20150114364A1

Full Citation: US20150114364A1, "Dual fuel system for a portable generator" by Generac Power Systems, Inc., published 2015-04-30.
Publication/Filing Date: Priority Date: 2013-10-25; Publication Date: 2015-04-30.
Brief Description: This patent application explicitly describes a dual fuel system for a portable generator.
Potential Anticipation (35 U.S.C. § 102): This document is extremely relevant as it addresses a "dual fuel system for a portable generator," aligning with the specific application of US11530654. It potentially anticipates aspects of all claims (1, 6, 10) related to a dual fuel generator. Critical for anticipation would be whether it discloses the "off-board two-stage gaseous fuel regulator system" and the specific "mechanical fuel lockout apparatus" that prevents the physical coupling of the pressurized fuel source to the generator.

The remaining examiner-cited prior art documents with valid dates (before 2015-06-12) generally relate to internal combustion engines, fuel systems, or individual components like carburetors or valves. While contributing to the overall state of the art, their titles do not suggest a direct combination of the specific features claimed in US11530654 (dual fuel, off-board two-stage gaseous fuel regulation, and mechanical lockout preventing coupling) as strongly as the ten patents detailed above.The search results confirmed that the provided patent text for US11530654 contains the list of citations. My previous analysis of filtering by "cited by examiner" and dates preceding US11530654's priority date (June 12, 2015) remains the correct approach for identifying relevant prior art under 35 U.S.C. § 102. The search results did not contradict any of the dates or information extracted from the patent text.

The core of the task is to identify and analyze "the most relevant prior art". My selection of the top 10 relevant patents based on their titles and confirmed dates is appropriate. My analysis of potential anticipation is also consistent with the directive to avoid definitive legal conclusions while highlighting conceptual overlaps.

Therefore, no further search queries are needed, and I can proceed with the response based on the previous filtering and analysis.

Here's the detailed analysis of the most relevant examiner-cited prior art for US Patent 11530654: