Diamondback Energy → Endeavor Energy Resources
Diamondback paid about $26bn including net debt, in shares and cash, for Endeavor Energy Resources, the family-owned Permian producer founded by Autry Stephens, handing Endeavor's owners nearly 40% of the combined company.
Diamondback bought the largest privately held Permian Basin operator, for combined net production of about 816,000 barrels of oil equivalent a day.
- Value
- $26B
- Announced
- February 2024
- Completed
- September 2024
- Sector
- Energy
- Deal type
- acquisition
- Acquirer
- Diamondback Energy (United States)
- Target
- Endeavor Energy Resources (United States)
Why it mattered
Autry Stephens built Endeavor from an 80-acre first purchase in the Spraberry Trend of West Texas, starting in 1979, into one of the largest private oil producers in the continental United States. After he was diagnosed with prostate cancer he sold it, through an auction, to give his family liquidity. The winner was Diamondback, whose Midland headquarters stood across the street from Endeavor's. The agreement of 12 February 2024 offered about 117.3 million Diamondback shares and $8bn in cash, leaving Endeavor's owners with about 39.5% of a company with some 838,000 net acres, 816,000 barrels of oil equivalent a day and about 6,100 drilling locations that break even below $40 oil. Diamondback promised $550m of annual synergies and cut its shareholder payout from 75% to at least 50% of free cash flow to repay the debt.
Two obstacles followed. Shareholders sued in Delaware over a stockholders' agreement that would have barred the Endeavor owners from selling to activists and required them to vote for the board's nominees; Diamondback removed those terms in March. The Federal Trade Commission, which made ExxonMobil's purchase of Pioneer Natural Resources conditional on barring Pioneer's former chief executive from its board, issued a second request in April but let the waiting period expire on 9 September 2024. The deal closed the next day, less than a month after Stephens died, with about $7.1bn paid in cash.
What it left behind
Former Endeavor holders offered 11.27 million shares within days, Diamondback buying back 2 million of them. In 2025 Diamondback moved Endeavor's royalty business, 1979 Royalties, to its royalty affiliate Viper Energy for $873m in cash plus Viper units, and sold about $1.7bn of non-core assets, including Endeavor's water business — while still buying, adding Double Eagle IV's Midland Basin acreage for $3.1bn in cash and 6.84 million shares in April 2025. Production rose 54% in 2025, with Endeavor accounting for 41% of the increase. At the end of 2025 Endeavor's former owners held about 35.8% of Diamondback and consent rights over certain actions, and by February 2026 Kaes Van't Hof had succeeded Travis Stice as chief executive.
Paying a founder's family in stock makes it a permanent constituency: the price is agreed once, but voting, consent and lock-up terms are lived with for years, and courts will read them closely.