The issues in this royalties-calculation dispute are (1) whether the producer's distribution of overriding royalties based on "amount realized" prohibits the producer from deducting post-production costs after delivery and (2) whether the merger-by-deed doctrine applies to govern the producer's obligation to an affiliate assigned overriding royalties by the original royalty-interest holder by superseding that assigning interest-holder's earlier agreements with the producer.

This suit involves the interpretation of a mineral lease and asks (1) whether the lease's offset production clause created a general duty to protect against all drainage, even when the allegedly draining well did not trigger the duty; (2) whether the court of appeals relied on an argument barred by res judicata; (3) whether there was a fact dispute about the existence of drainage; and (4) whether the court of appeals erred by reversing a summary judgment on unchallenged claims.