Stephens Greth Family Foundation
The Stephens Greth Family Foundation is a private grantmaking foundation established in 2024 by the family of the late Autry Stephens, founder of Texas-based oil producer Endeavor Energy Resources. The foundation received an initial contribution from Stephens’s estate worth approximately $2 billion derived from proceeds of the $26 billion sale of Endeavor Energy Resources to Diamondback Energy, which was completed months before Stephens’s death. As of 2024, Lyndal Stephens Greth, Autry Stephens’s daughter and former chair of Endeavor, was the sole listed officer as well as the director and president of the foundation, which due to its endowment was immediately noted as one of the largest family foundations in the United States at the time of its formation. The foundation did not disclose any 2024 grants; however, it was expected to begin grantmaking of up to $100 million annually. Among the first announced recipients of the foundation’s giving were the University of Texas and the SPCA of Texas, an animal welfare group. 1 2 3 4 5 6
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Background
Autry Stephens founded Endeavor Energy Resources in 1979 after earning a petroleum engineering degree from the University of Texas-Austin and earlier stints in the oil and gas industry. Stephens grew Endeavor into a major independent producer in the Permian Basin, operating more than 500,000 acres and producing significant volumes of oil and gas. The company remained privately held until its $26 billion acquisition by Diamondback Energy in 2024. 6
Autry Stephens died in August 2024 at age 86, six months after the sale of his company was announced. Following his passing, his daughter Lyndal Stephens Greth, who was the chair of Endeavor’s board, oversaw the final stages of the sale and the establishment of the family foundation. The foundation was incorporated in Midland, Texas, the longtime headquarters of Endeavor, and received tax-exempt status from the Internal Revenue Service (IRS) in September 2024. The foundation’s endowment of $2 billion placed it as one of the top 100 private foundations in the United States in terms of assets at the time of its founding. 7 4 2
Lyndal Stephens Greth was the only listed officer of the foundation according to its initial tax filings, simultaneously holding the roles of director, president, secretary, and treasurer. The foundation reported no 2024 grants or expenses of any kind, receiving tax exempt status in September 2024. 1
Activities
The foundation’s 2024 tax return, covering the period of its formation through December 31st, 2024, reported zero charitable disbursements. Grantmaking activity began to appear in public announcements during 2025. 1
In October 2025, the foundation committed $8 million to the SPCA of Texas, an animal welfare group, as part of the organization’s “Care Unleashed” $31 million capital campaign. Of that amount, $5 million was designated for the construction of a new building on the SPCA of Texas campus, and $3 million was allocated to program support. The gift resulted in the SPCA’s Dallas campus being renamed the Stephens Greth Foundation Campus. 8
The foundation also provided funding in 2025 to build a new building at the University of Texas at Austin’s Cockrell School of Engineering, to be named the Autry C. Stephens Engineering Discovery Building, which was intended to house the engineering school’s Hildebrand Department of Petroleum and Geosystems Engineering and McKetta Department of Chemical Engineering. 6