**
EXHIBIT 99.1 

January 17, 2023 

Ms. Kameron Fivecoat 

Reserves Manager 

XTO Energy Inc. 

22777 Springwoods Village Parkway 

Spring, TX 77389 

 
  Re:  Underlying Properties (100%)    Relating to the Cross Timbers Royalty Trust    Reserves and Future Net Revenues    As of December 31, 2022    SEC Price Case
Dear Ms. Fivecoat: 

At your request, Millerand Lents, Ltd. (M&L) estimated the proved reserves and future net revenues as of December 31, 2022, attributable to the XTO Energy Inc. (XTO) interest in certain oil and gas properties prior to inclusion in the Cross Timbers Royalty Trust,i.e., Underlying Properties (100%). The Underlying Properties (100%) include royalty interest and working interest properties from which net profits interests were conveyed to the Cross Timbers Royalty Trust. The properties consist of approximately3,212 leases and 15,373 wells located primarily in New Mexico, Oklahoma, and Texas. The aggregate results of M&L’s evaluations are as follows: 

 
   **Net Reserves**   **Future Net Revenues** 
**Reserves Category**
  **Oil and****Condensate****MBBL**   **Gas****MMCF**   **Undiscounted****M$**   **Discounted****at****10% Per Year****M$** 
**Royalty Interest Properties**

** **

Proved Developed Producing
   388    16,279    159,917    81,213   
 

 
   
 

 
   
 

 
   
 

 
 
**Total Proved**
  ** ****388**** **  ** ****16,279**** **  ** ****159,917**** **  ** ****81,213**** **  
 

 
   
 

 
   
 

 
   
 

 
 
**Working Interest Properties**

** **

Proved Developed Producing
   1,425    622    64,926    34,650   
 

 
   
 

 
   
 

 
   
 

 
 
**Total Proved**
  ** ****1,425**** **  ** ****622**** **  ** ****64,926**** **  ** ****34,650**** **  
 

 
   
 

 
   
 

 
   
 

 
 
**Total Royalty and Working Interest Properties**

** **

Proved Developed Producing
   1,813    16,901    224,843    115,863   
 

 
   
 

 
   
 

 
   
 

 
 
**Total Proved**
  ** ****1,813**** **  ** ****16,901**** **  ** ****224,843**** **  ** ****115,863**** **  
 

 
   
 

 
   
 

 
   
 

 
 **

Underlying Properties (100%) 

Relating to the Cross Timbers Royalty Trust 

January 17, 2023 

Oil and condensate volumes are expressed inthousand barrels (MBBL). Gas volumes are expressed in million cubic feet (MMCF). Future net revenues are expressed in thousand dollars (M$). 

The report wasprepared for the use of XTO in its financial and reserves reporting and was completed on January 17, 2023. M&L performed evaluations, which are designated as the SEC Price Case, using price and expense premises specified by XTO anddescribed in detail on Appendix 1. 

Proved reserves and future net revenues were estimated in accordance with the provisions contained in Securities and ExchangeCommission Regulation S-X, Rule 4-10(a). The Securities and Exchange Commission definition of proved reserves is shown on Appendix 2 (not included). Gas volumes for eachproperty are stated at the pressure and temperature bases appropriate for the sales contract or state regulatory authority; therefore, some of the aggregated totals may be stated at a mixed pressure base. No provisions for the possible consequences,if any, of product sales imbalances were included in M&L’s projections since M&L received no relevant data. Estimates of future net revenues and discounted future net revenues are not intended and should not be interpreted to representfair market values for the estimated reserves. In M&L’s projections, future costs of abandoning facilities and wells were assumed to be offset by salvage values. Estimated costs, if any, for restoration of producing properties to satisfyenvironmental standards are beyond the scope of this assignment. 

Following Appendix 2 (not included) is a list of exhibits that include annual projections offuture production and net revenues for each state, interest type, and reserves category. Also included in the exhibits are one-line summaries showing the proved reserves and future net revenues for eachproperty in the total royalty trust, in the working interest category, in the royalty interest category, and in each state. These exhibits should not be relied upon independently of this narrative. 

The proved developed producing reserves and production forecasts were estimated by production decline extrapolations, water-oilratio trends, P/Z declines, or in a few cases, by volumetric calculations. For some properties with insufficient performance history to establish trends, M&L estimated future production by analogy with other properties with similarcharacteristics. The past performance trends of many properties were influenced by production curtailments, workovers, waterfloods, and/or infill drilling. Actual future production may require that M&L’s estimated trends be significantlyaltered. Reserves estimates from volumetric calculations and from analogies are often less certain than reserves estimates based on well performance obtained over a period during which a substantial portion of the reserves was produced. 

The estimated proved developed nonproducing reserves can be produced from existing well bores but require capital costs for recompletions or for pipeline connections.These proved developed nonproducing reserves estimates were based on analogies with other wells that commercially produce from the same formation in the same field. The timing of initial production was provided to M&L by XTO. When actualproduction history is available for these nonproducing reserves, M&L’s reserves estimates may be significantly revised. 

The estimated proved undevelopedreserves require significant capital expenditures, such as for planned drilling and completion costs. The proved undeveloped reserves estimates for infill wells are based on analogies to similar infill wells in the same field and/or the productionhistories of offset wells in the same field. As actual results of the planned drilling become available, M&L’s reserves estimates may be significantly revised. 

The data employed in M&L’s estimations of proved reserves and future net revenues were provided by XTO. The current expenses for each lease were obtained fromoperating statements provided by XTO except for certain leases where XTO deducted items considered by XTO to be nonrecurring expenditures. No overhead was included for those properties operated by XTO. For some properties, such as large waterfloods,XTO assumed a decline in operating costs due to depleting production that was derived by forecasting a decrease in the property well count. The data provided to M&L by XTO, including, but not limited to, graphical representations and tabulationsof past production performance, well tests and 

Underlying Properties (100%) 

Relating to the Cross Timbers Royalty Trust 

January 17, 2023 

 

pressures, ownership interests, prices, and operating costs were accepted as represented and were considered appropriate for the purpose of this report. M&L employed all methods, data,procedures, and assumptions considered necessary and appropriate in utilizing the data provided to prepare this report. 

The evaluations presented in this report,with the exceptions of those parameters specified by others, reflect M&L’s informed judgments and are subject to the inherent uncertainties associated with interpretation of geological, geophysical, and engineering information. Theseuncertainties include, but are not limited to, (1) the utilization of analogous or indirect data and (2) the application of professional judgments. Government policies and market conditions different from those employed in this study maycause (1) the total quantity of oil, natural gas liquids, or gas to be recovered, (2) actual production rates, (3) prices received, or (4) operating and capital costs to vary from those presented in this report. At this time,M&L is not aware of any regulations that would affect XTO’s ability to recover the estimated reserves. 

Miller and Lents, Ltd. is an independent oil andgas consulting firm. No director, officer, or key employee of Miller and Lents, Ltd. has any financial ownership in XTO Energy Inc. or any related company. M&L’s compensation for the required investigations and preparation of this report isnot contingent on the results obtained and reported, and it has not performed other work that would affect M&L’s objectivity. Production of this report was supervised by Jennifer A. Godbold, P.E., an officer of the firm who is a licensedProfessional Engineer in the State of Texas and is professionally qualified, with more than ten years of relevant experience, in the estimation, assessment, and evaluation of oil and gas reserves. 

M&L’s work papers and data are in its files and available for review upon request. If you have any questions regarding the above, or if M&L can be offurther assistance, please call. 

 
Very truly yours,MILLER AND LENTS, LTD.Texas Registered Engineering Firm No. F-1442
/S/ JENNIFER A. GODBOLD
Jennifer A. Godbold, P.E.Senior Vice President

Appendix 1 

Cross Timbers Royalty Trust (100%) 

SEC PRICE CASE

 
A.  Oil Price  Average price during the 12-month period prior to 12/31/22 determined as the arithmetic average of the first-day-of-the-month price for each month during the year 2022. The average price was based on the West Texas Intermediate benchmark price. The arithmeticaverage of the first-day-of-the-month benchmark prices is $93.67 per barrel and is heldconstant through the life of the property. The average realized price, after appropriate adjustments, is $93.06 per barrel.B.  Gas Price  Average price during the 12-month period prior to 12/31/22 determined as the arithmetic average of the first-day-of-the-month price for each month during the year 2022. The average price was based on the Henry Hub benchmark price. The arithmetic average of the first-day-of-the-month benchmark price is $6.357 per MMBTU and is held constant through thelife of the property. The average realized price, after appropriate adjustments is $8.60 per MCF.C.  Operating Costs  Current expenses held constant through the life of the property. For some properties, expenses included a variable component that was a constant cost per unit of gas production and a fixed component that was a constant cost per wellcompletion.D.  Discount Rate  10% per year.