I noticed after signing the DO in 2009 that the RI Payments on Gas/Casinghead Production Quantity (Volume) didn't match the Texas RRC Lease# under "Disposition Details" Production with Code 3 (means Processing Plant) and notified the O&G Company who stated that the remaining Gas was most likely used in the Field.
For Example: Texas RRC shows Casinghead (MCF) under "Disposition Details" with Code 3 total Production 5,000 but they only paid 2,500 or less (1/2 or 1/3 of total Production Disposition).
The Texas Railroad Commission said that it should only be off by 10% (not 50-70%).
Also, I believe the County Appraisal District charges Royalty Owner's based on the Gas/Casinghead Production Disposition with Code 3.