HOUSTON, October 11, 2025 — 406 Energy, LLC (“406”) is proud to announce its formation with an initial equity commitment from NGP Natural Resources XIII, L.P. and the 406 Energy management team.
406 Energy was founded by four partners: Mark Graeve, Tom Kastens, Josh Sigler, and Eric Matus. The 406 management team has a history of working together, most notably as members of the pre-asset team at XCL Resources: an upstream oil and gas company that grew production to become the largest oil producer in Utah. 406 plans to focus on developing upstream oil and gas opportunities.
Patrick McWilliams, Partner at NGP, commented, “NGP is excited to partner with 406 Energy. The founders bring a combination of leading-edge reservoir characterization and data analytics, which, when combined, provide differentiated insights that are highly investable. The technical and operating capabilities at 406 are only surpassed by the team’s character and winning culture. We look forward to supporting the 406 team as they build a durable, high-return upstream platform.”
Mark Graeve commented, “We are proud to partner with NGP to build an upstream business aligned with a common vision. We are grateful to NGP for this opportunity and all our former colleagues and field personnel whose hard work advanced the industry leading teams we have been part of.”