Ownership of the Kuparuk River unit has remained the same over the years — only some of the names have changed.
Field operator ARCO Alaska reported eight other companies involved in 1981 unitization discussions: BP Alaska Exploration, Sohio Alaska Petroleum and Union Oil Company of California were the other major owners; smaller interests were held by Exxon, Mobil, Phillips Petroleum, Chevron U.S.A. and Amoco Production.
All, through purchase or merger, are still involved:
Phillips bought ARCO Alaska, then merged with Conoco and today operates the field as ConocoPhillips Alaska.
Both Sohio and Amoco are now part of BP.
Chevron has purchased Unocal.
Exxon and Mobil have merged.
