Part of what I do for clients as a Texas oil and gas attorney is to calculate oil and gas royalties so that they can be sure they are being paid correctly. I thought it might be useful to you to explain how an ownership percentage and royalty are calculated.
1. First, we take your percentage of mineral ownership in the land in question, and we multiply that by the number of surface acres in your entire tract. The resulting number is your net mineral acres. For example, if two relatives together own a one-half interest in a forty acre tract, or ½ times 40, they have twenty net mineral acres. 2. Secondly, if the land is located in a pooling unit, (sometimes also called a pro-ration unit), we multiple the total number of acres in the tract by a pro-ration fraction. The reason for this is that each royalty owner in a pooling unit is only entitled to their proportionate share of the oil or gas produced by the entire pooling unit. A pooling unit is an area around a well that is set by the Texas Railroad Commission, and is intended to approximate the area drained by a producing well. Pooling units can range in size from 80 to 640 acres or more. For example, for a forty acre tract that is located in a 320 acre pooling unit, that forty acre tract is entitled to 40/320, or 0.12500, of the minerals (whether oil or gas or both) produced by that 320 acre unit.
3. Third, we multiply that result by the royalty fraction in the oil and gas lease you signed.