P, owners of a 30-acre parcel of land, entered into a 10-year written lease with D. D was given the right to 'mine, process, and remove sand, gravel, and/or field dirt' from the subject land. D was obligated to pay P $.25 per cubic yard for the materials removed from the land during the first five years of the lease and $.35 per cubic yard during the remaining five years of the lease. A nonassignment clause was in the lease: 'The Grantee agrees not to assign or sub-let this lease, without the permission of the Grantors.' Through 1986, D mined the property and P got paid. In 1987, Williams Brothers purchased all of the assets of D. D was unsuccessful in obtaining P's consent to an assignment of the lease. On March 11, 1987, an acquisition agreement was executed between D and Williams Brothers, whereby Williams agreed to purchase the assets and to assume the liabilities of D. After the acquisition P noticed that Williams Brothers equipment and employees were being used to mine the property. P sought a declaration that D had assigned the lease to Williams Brothers in violation of the lease provisions. The trial court granted D's motion for a directed verdict pursuant to Rule 50(a), A.R.Civ.P. P appealed.