Phillips Petroleum Co. v. Curtis

Phillips Petroleum (plaintiff) held an oil-and-gas lease from the Curtises (defendants) that would terminate unless drilling began or delay rental was paid annually by October 4; Phillips paid on time the first year but missed the second year's deadline solely due to an inadvertent mistake by one of its own employees, despite being otherwise willing and able to pay. When Phillips discovered the error months later and tendered payment, the Curtises refused it and claimed the lease had already terminated; the trial court agreed, and Phillips appealed seeking equitable relief.