By Chris Mathews, January 26, 2026 05:03 PM CST

Private equity-backed firms Wellspring Energy Resources and Mesa Mineral Partners are growing their Williston Basin portfolios.

Waveland Energy Partners completed the sale of non-operated working interest assets to Wellspring and mineral assets to Mesa. Financial terms of the deals were not disclosed.

Both Wellspring and Mesa are portfolio companies of NGP Energy Capital.

Wellspring invests in development opportunities and non-op working interests across North America. The acquisition from Waveland included core Williston assets in North Dakota and Montana producing 1,480 boe/d.

Mesa Mineral Partners has historically focused on the Haynesville Shale but started building a Williston position last year through its new entity Mesa Minerals IV, President and CEO Darin Zanovich said.

The Waveland minerals assets included liquids-weighted net production of 210 boe/d and 5,800 net royalty acres. Mesa also picked up royalty interests in over 600 producing wells.

After completing the Waveland transaction and multiple ground game deals last year, Mesa holds more than 13,000 net royalty acres in the Williston Basin. The company also continues to add to its royalty portfolios in the Haynesville Shale and Permian Basin, Zanovich said.

Waveland was advised by Stephens Inc. in connection with the Williston asset sales. Operators on Waveland’s Williston assets include Continental Resources, ExxonMobil, Hess Corp., Chord Energy and EOG Resources.

Mesa’s predecessor company, Mesa III, holds around 6,000 net royalty acres in the Permian and 16,000 in the Haynesville. Both Mesa I and Mesa II built Haynesville mineral positions and exited through transactions with Franco-Nevada Corp.

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