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UNITED STATES SECURITIES AND
EXCHANGE COMMISSION Washington, D.C. 20549   Form 10-K    ☒
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2017 OR  ☐
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934  For the transition period from  to
.

Commission File No. 1-10982 Cross Timbers Royalty Trust (Exact name of registrant as specified in its charter)  Texas

75-6415930(State or other jurisdiction of
incorporation or organization)

(I.R.S. Employer Identification No.)c/o Corporate Trustee:
Simmons Bank P.O. Box
962020 Fort Worth, Texas

76162-2020(Address of principal executive offices)

(Zip Code) Registrants telephone number, including area code (at the office of the Corporate Trustee): (855) 588-7839 Securities registered pursuant to Section 12(b) of the Act:  Title of each
class

Name of each exchange on which
registeredUnits of Beneficial Interest

New York Stock Exchange Securities registered pursuant to Section 12(g) of the Act: None Indicate by check mark
if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ☐        No  ☒ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the
Act.    Yes  ☐        No  ☒ Indicate by check
mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file
such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  ☒        No  ☐ Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data
File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to
submit and post such files).    Yes  ☐        No  ☐ Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is
not contained herein, and will not be contained, to the best of registrants knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K.    ☒ Indicate by check mark whether the
registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of large accelerated filer,
accelerated filer, smaller reporting company, and emerging growth company in Rule 12b-2 of the Exchange Act. (Check one):  Large accelerated filer  ☐

Accelerated filer  ☒

Non-accelerated filer  ☐

Smaller reporting company  ☐(Do not check if a smaller reporting company)

Emerging Growth Company  ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended
transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.    ☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the
Act).    Yes  ☐        No  ☒ The aggregate
market value of units of beneficial interest held by non-affiliates of the registrant at June 30, 2017 (the last business day of the registrants most recently completed second fiscal quarter) was
approximately $91.9 million. The number of units of beneficial interest outstanding as of February 15, 2018 was 6,000,000.




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CROSS TIMBERS ROYALTY TRUST 2017 ANNUAL REPORT ON FORM 10-K TABLE OF CONTENTS  PageGlossary of Terms


1PART IItem 1.

Business


2Item 1A.

Risk Factors


4Item 1B.

Unresolved Staff Comments


8Item 2.

Properties


9Item 3.

Legal Proceedings


18Item 4.

Mine Safety Disclosures


18PART IIItem 5.

Market for Units of the Trust, Related Unitholder Matters and Trust Purchases
 of Units


19Item 6.

Selected Financial Data


19Item 7.

Trustees Discussion and Analysis of Financial Condition and Results of
 Operations


20Item 7A.

Quantitative and Qualitative Disclosures about Market Risk


26Item 8.

Financial Statements and Supplementary Data


26Item 9.

Changes in and Disagreements with Accountants on Accounting and Financial Disclosure


39Item 9A.

Controls and Procedures


39Item 9B.

Other Information


39PART IIIItem 10.

Directors, Executive Officers and Corporate Governance


40Item 11.

Executive Compensation


40Item 12.

Security Ownership of Certain Beneficial Owners and Management and Related Unitholder
Matters


40Item 13.

Certain Relationships and Related Transactions, and Director
Independence


41Item 14.

Principal Accountant Fees and Services


41PART IVItem 15.

Exhibits and Financial Statement Schedules


42  i




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GLOSSARY OF TERMS The following is a glossary of certain defined terms used in this Annual Report on Form 10-K. GLOSSARY  Bbl
Barrel (of oil)  Bcf
Billion cubic feet (of natural gas)  BOE
Barrel of oil equivalent  Mcf
Thousand cubic feet (of natural gas)  MMBtu
One million British Thermal Units, a common energy measurement  net proceeds
Gross proceeds received by XTO Energy from sale of production from the underlying properties, less applicable costs, as defined in the net profits interest conveyances  net profits income
Net proceeds multiplied by the applicable net profits percentage of 75% or 90%, which is paid to the Trust by XTO Energy. Net profits income is referred to as royalty income for income tax purposes.  net profits interest
An interest in an oil and gas property measured by net profits from the sale of production, rather than a specific portion of production. The following defined net profits interests were conveyed to the Trust from the underlying properties:  90% net profits interestsinterests that entitle the Trust to receive 90% of the net proceeds from the underlying properties that are substantially all royalty or overriding royalty interests in Texas,
Oklahoma and New Mexico  75% net profits interestsinterests that entitle the Trust to receive 75% of the net proceeds from the underlying properties that are working interests in Texas and Oklahoma  royalty interest (and overriding royalty interest)
A non-operating interest in an oil and gas property that provides the owner a specified share of production without any production expense or development costs  underlying properties
XTO Energys interest in certain oil and gas properties from which the net profits interests were conveyed. The underlying properties include royalty and overriding royalty interests in producing and nonproducing properties in Texas,
Oklahoma and New Mexico, and working interests in producing properties located in Texas and Oklahoma.  working interest
An operating interest in an oil and gas property that provides the owner a specified share of production that is subject to all production expense and development costs  1




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PART I  Item 1.
Business Cross Timbers Royalty Trust (the Trust) is an
express trust created under the laws of Texas pursuant to the Cross Timbers Royalty Trust Indenture entered into on February 12, 1991 between predecessors of XTO Energy Inc. (formerly known as Cross Timbers Oil Company), as grantors, and NCNB
Texas National Bank, as Trustee. On January 9, 2014, the successor of NCNB Texas National Bank, U.S. Trust, Bank of America Private Wealth Management, a division of Bank of America, N.A., gave notice to unitholders that it would resign as
Trustee. At the special meeting of the Trusts unitholders held on June 20, 2014, the unitholders of the Trust voted to approve the proposal to appoint Southwest Bank as successor Trustee of the Trust effective August 29, 2014. The
principal office of the Trust is P.O. Box 962020, Fort Worth, TX 76162-2020. (telephone number 855-588-7839). Effective October 19, 2017, Simmons First National Corporation (SFNC) completed its acquisition of First Texas BHC, Inc., the
parent company of Southwest Bank, the Trustee of the Trust. SFNC is the parent of Simmons Bank. SFNC merged Southwest Bank with Simmons Bank effective February 20, 2018. Simmons Bank (the Trustee) is now the Trustee of the Trust. The Trusts internet web site is www.crt-crosstimbers.com. We make available free of
charge, through our web site, our Annual Report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and all
amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934. These reports are accessible through our internet web site as soon as reasonably practicable after we electronically file
such material with, or furnish it to, the Securities and Exchange Commission. Information on our website is not incorporated into this report. On February 12, 1991, the predecessors of XTO Energy conveyed defined net profits interests to the Trust under five separate conveyances:  

one in each of the states of Texas, Oklahoma and New Mexico, to convey a 90% defined net profits interest carved out of substantially all royalty and overriding royalty interests owned by the predecessors in those
states, and  

one in each of the states of Texas and Oklahoma, to convey a 75% defined net profits interest carved out of specific working interests owned by the predecessors in those states. The conveyance of these net profits interests was effective for production from October 1, 1990. The net profits interests and the
underlying properties are further described under Item 2, Properties. In exchange for the net profits interests conveyed to the Trust,
the predecessors of XTO Energy received 6,000,000 units of beneficial interest of the Trust. Predecessors of XTO Energy distributed units to their owners in February 1991 and November 1992, and in February 1992, sold units in the Trusts
initial public offering. Units are listed and traded on the New York Stock Exchange under the symbol CRT. XTO Energy currently is not a unitholder of the Trust. On June 25, 2010, XTO Energy became a wholly owned subsidiary of Exxon Mobil Corporation. Under the terms of each of the five conveyances, the Trust receives net profits income from the net profits interests generally on the last
business day of each month. Net profits income is determined by XTO Energy by multiplying the net profit percentage (90% or 75%) times net proceeds from the underlying properties for each conveyance during the previous month. Net proceeds are the
gross proceeds received from the sale of production, less production costs, as defined in the conveyances. For the 90% net profits interests and the 75% net profits interests, production costs generally include applicable property taxes,
transportation, marketing and other  2




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charges. For the 75% net profits interests, production costs also include capital and operating costs paid (e.g., drilling, production and other direct costs of owning and operating the
property) and a monthly overhead charge that is adjusted annually. The monthly overhead charge at December 31, 2017 was $39,245 ($29,434 net to the Trust). XTO Energy deducts an overhead charge as operator of the Hewitt Unit. As of
December 31, 2017, monthly overhead attributable to the Hewitt Unit was $5,607 ($4,205 net to the Trust). If production costs exceed gross proceeds for any conveyance, this excess is carried forward to future monthly computations of net
proceeds until the excess costs (plus interest accrued as specified in the conveyances) are completely recovered. Excess production costs and related accrued interest from one conveyance cannot be used to reduce net proceeds from any other
conveyance. For further information on excess costs, see Note 7 to Financial Statements under Item 8, Financial Statements and Supplementary Data. The Trust is not liable for any production costs or liabilities attributable to the underlying properties. If at any time the Trust receives
net profits income in excess of the amount due, the Trust is not obligated to return such overpayment, but future net profits income payable to the Trust will be reduced until the overpayment, plus interest at the prime rate, is recovered. Approximately 15 of the underlying royalty interests in New Mexico burden working interests in properties operated by XTO Energy. XTO Energy
operates the Hewitt Unit which is one of the properties underlying the Oklahoma 75% net profits interests. Other than these properties, XTO Energy and ExxonMobil do not operate or control any of the underlying properties or related working
interests. As a working interest owner, XTO Energy can generally decline participation in any operation and allow consenting parties to
conduct such operations, as provided under the operating agreements. XTO Energy also can assign, sell, or otherwise transfer its interest in the underlying properties, subject to the net profits interests, or can abandon an underlying property that
is a working interest if it is incapable of producing in paying quantities, as determined by XTO Energy. To the extent allowed, XTO
Energy is responsible for marketing its production from the underlying properties under existing sales contracts or new arrangements on the best terms reasonably obtainable in the circumstances. Net profits income received by the Trust on or before the last business day of the month is generally attributable to oil production two
months prior and gas production three months prior. The monthly distribution amount to unitholders is determined by: Adding   (1)
net profits income received, (2)
estimated interest income to be received on the monthly distribution amount, including an adjustment for the difference between the estimated and actual interest received for the prior monthly distribution amount, (3)
cash available as a result of reduction of cash reserves, and (4)
other cash receipts, then Subtracting   (1)
liabilities paid and (2)
the reduction in cash available due to establishment of or increase in any cash reserve. The
monthly distribution amount is distributed to unitholders of record within ten business days after the monthly record date. The monthly record date is generally the last business day of the month. The Trustee calculates the monthly distribution
amount and announces the distribution per unit at least ten days prior to the monthly record date.  3




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The Trustee may establish cash reserves for contingencies. Cash held for such reserves, as
well as for pending payment of the monthly distribution amount, may be invested in federal obligations or certificates of deposit of major banks. The Trustees function is to collect the net profits income from the net profits interests, to pay all Trust expenses and to pay the
monthly distribution amount to unitholders. The Trustees powers are specified by the terms of the indenture. The Trust cannot engage in any business activity or acquire any assets other than the net profits interests and specific short-term
cash investments. The Trust has no employees since all administrative functions are performed by the Trustee. Approximately 62% of the
net profits income received by the Trust during 2017 was attributable to natural gas, as well as 45% of the Trusts estimated future net cash flows from proved reserves at December 31, 2017 (based on estimated future net cash flows using 12-month average oil and gas prices, based on the
first-day-of-the-month price for each month in the period). There is generally a greater
demand for gas during the winter. Otherwise, Trust income is not subject to seasonal factors, nor dependent upon patents, licenses, franchises or concessions. The Trust conducts no research activities. The oil and gas industry is highly competitive in all its phases. Operators of the properties in which the Trust holds interests encounter
competition from other oil and gas companies and from individual producers and operators. Oil and natural gas are commodities, for which market prices are determined by external supply and demand factors. Current market conditions are not
necessarily indicative of future conditions.  Item 1A.
Risk Factors The following factors could cause actual results to
differ materially from those contained in forward-looking statements made in this report and presented elsewhere by the Trustee from time to time. Such factors may have a material adverse effect upon the Trusts financial condition,
distributable income and changes in trust corpus. The following discussion of risk factors should be read in conjunction with the
financial statements and related notes included under Item 8, Financial Statements and Supplementary Data. Because of these and other factors, past financial performance should not be considered an indication of future performance. The market price for the Trust units may not reflect the value of the net profits interests held by the Trust. The public trading price for the Trust units tends to be tied to the recent and expected levels of cash distributions on the Trust units. The
amounts available for distribution by the Trust vary in response to numerous factors outside the control of the Trust or XTO Energy, including prevailing prices for oil and natural gas produced from the underlying properties. The market price of the
Trust units is not necessarily indicative of the value that the Trust would realize if the net profits interests were sold to a third party buyer. In addition, such market price is not necessarily reflective of the fact that, since the assets of the
Trust are depleting assets, a portion of each cash distribution paid on the Trust units should be considered by investors as a return of capital, with the remainder being considered as a return on investment. There is no guarantee that distributions
made to a unitholder over the life of these depleting assets will equal or exceed the purchase price paid by the unitholder. Oil and natural gas
prices fluctuate due to a number of uncontrollable factors, and any decline will adversely affect the net proceeds payable to the Trust and Trust distributions. The Trusts monthly cash distributions are highly dependent upon the prices realized from the sale of natural gas and oil. Oil and natural
gas prices can fluctuate widely on a month-to-month basis in response to a variety of factors that are beyond the control of the Trust and XTO Energy. Factors that
contribute to price fluctuations include instability in oil-producing regions, worldwide economic conditions, weather conditions, the supply of domestic and foreign oil, natural gas and natural gas liquids,
consumer demand, the price and availability of  4




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alternative fuels, the proximity to, and capacity of, transportation facilities and the effect of worldwide energy conservation measures. Moreover, government regulations, such as regulation of
natural gas transportation and price controls, can affect product prices. A significant decline in oil or natural gas prices could have a material adverse effect on the amount of oil and natural gas that is economic to produce, Trust net profits
(and therefore cash available for distribution to unitholders) and proved reserves attributable to the Trusts interests. The volatility of energy prices reduces the predictability of future cash distributions to Trust unitholders. Higher production expense and/or development costs, without concurrent increases in revenue, will directly decrease the net proceeds payable to the
Trust from the properties underlying the 75% net profits interests. Production expense and development costs are deducted in the
calculation of the Trusts share of net proceeds from properties underlying the 75% net profits interests. Accordingly, higher or lower production expense and development costs, without concurrent changes in revenue, will directly decrease or
increase the amount received by the Trust for its 75% net profits interests. If development costs and production expense for properties underlying the 75% net profits in a particular state exceed the production proceeds from the properties, (as was
the case with respect to the properties underlying the Texas working interests for all of 2016 and 2017 and with respect to the properties underlying the Oklahoma working interests for all of 2016 and the first three quarters of 2017) the Trust will
not receive net profits income for those properties until future net proceeds from production in that state exceed the total of the excess costs plus accrued interest during the deficit period. Development activities may not generate sufficient
additional revenue to repay the costs. Proved reserve estimates depend on many assumptions that may turn out to be inaccurate. Any material
inaccuracies in reserve estimates or underlying assumptions could cause the quantities and net present value of the reserves to be overstated. Estimating proved oil and gas reserves is inherently uncertain. Petroleum engineers consider many factors and make assumptions in estimating
reserves and future net cash flows. Those factors and assumptions include historical production from the area compared with production rates from similar producing areas, the effects of governmental regulation, assumptions about future commodity
prices, production expense and development costs, taxes and capital expenditures, the availability of enhanced recovery techniques and relationships with landowners, working interest partners, pipeline companies and others. Lower oil and gas prices
generally cause lower estimates of proved reserves. Ultimately, actual production, revenues and expenditures for the underlying properties will vary from estimates and those variances could be material. Because the Trust owns net profits interests,
it does not own a specific percentage of the oil and gas reserves. Estimated proved reserves for the net profits interests are based on estimates of reserves for the underlying properties and an allocation method that considers estimated future net
proceeds and oil and gas prices. Because Trust reserve quantities are determined using an allocation formula, increases or decreases in oil and gas prices can significantly affect estimated reserves of the 75% net profits interests. Operational risks and hazards associated with the development and operations of the underlying properties may decrease Trust distributions. There are operational risks and hazards associated with the production and transportation of oil and natural gas, including without limitation
natural disasters, blowouts, explosions, fires, leakage of oil or natural gas, releases of other hazardous materials, mechanical failures, cratering, and pollution. Any of these or similar occurrences could result in the interruption or cessation of
operations, personal injury or loss of life, property damage, damage to productive formations or equipment, damage to the environment or natural resources, or cleanup obligations. The operation of oil and gas properties is also subject to various
laws and regulations. Non-compliance with such laws and regulations could subject the operator to additional costs, sanctions or liabilities. The uninsured costs resulting from any of the above or similar
occurrences could be deducted as a production expense or development cost in calculating the net proceeds payable to the Trust from properties underlying the 75% net profits interests, and would therefore reduce Trust distributions by the amount of
such uninsured costs.  5




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Future net profits may be subject to risks relating to the creditworthiness of third parties. The Trust does not lend money and has limited ability to borrow money, which the Trustee believes limits the Trusts risk
from exposure to credit markets. The Trusts future net profits, however, may be subject to risks relating to the creditworthiness of the operators of the underlying properties and other purchasers of crude oil and natural gas produced from the
underlying properties. This creditworthiness may be impacted by the price of crude oil and natural gas. Trust unitholders and the Trustee have no
influence over the operations on, or future development of, the underlying properties. Because XTO Energy does not operate most of
the underlying properties, it is unable to significantly influence the operations or future development of the underlying properties. Neither the Trustee nor the Trust unitholders can influence or control the operation or future development of the
underlying properties. The failure of an operator to conduct its operations or discharge its obligations in a proper manner could have an adverse effect on the net proceeds payable to the Trust. Although XTO Energy and the other operators of the
underlying properties must adhere to the standard of a prudent operator, they are under no obligation to continue operating the properties. Neither the Trustee nor Trust unitholders have the right to replace an operator. The assets of the Trust represent interests in depleting assets and, if XTO Energy or any other operators developing the underlying properties do not
perform additional successful development projects, the assets may deplete faster than expected. Eventually, the assets of the Trust will cease to produce in commercial quantities and the Trust will cease to receive proceeds from such assets. The net proceeds payable to the Trust are derived from the sale of hydrocarbons from depleting assets. Future maintenance and
development projects on the underlying properties will affect the quantity of proved reserves and can offset the reduction in the depletion of proved reserves. The timing and size of these projects will depend on the market prices of oil and natural
gas. If the operator(s) of the properties do not implement additional maintenance and development projects, the future rate of production decline of proved reserves may be higher than the rate currently expected by the Trust. Because the net
proceeds payable to the Trust are derived from the sale of hydrocarbons from depleting assets, the portion of distributions to unitholders attributable to depletion may be considered a return on capital as opposed to a return on investment.
Distributions that are a return of capital will ultimately diminish the depletion tax benefits available to the unitholders, which could reduce the market value of the units over time. Eventually, the properties underlying the Trusts net
profits interest will cease to produce in commercial quantities and the Trust will, therefore, cease to receive any net proceeds therefrom. Terrorism and geopolitical hostilities could adversely affect Trust distributions or the market price of the Trust units. Terrorist attacks and the threat of terrorist attacks, whether domestic or foreign, as well as military or other actions taken in response,
cause instability in the global financial and energy markets. Terrorism and other geopolitical hostilities could adversely affect Trust distributions or the market price of the Trust units in unpredictable ways, including through the disruption of
fuel supplies and markets, increased volatility in oil and natural gas prices, or the possibility that the infrastructure on which the operators of the underlying properties rely could be a direct target or an indirect casualty of an act of terror. XTO Energy may transfer its interest in the underlying properties without the consent of the Trust or the Trust unitholders. XTO Energy may at any time transfer all or part of its interest in the underlying properties to another party. Neither the Trust nor the Trust
unitholders are entitled to vote on any transfer of the properties underlying the  6




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Trusts net profits interests, and the Trust will not receive any proceeds of any such transfer. Following any transfer, the transferred property will continue to be subject to the net
profits interests of the Trust, but the calculation, reporting and remitting of net proceeds to the Trust will be the responsibility of the transferee. XTO Energy or any other operator of any underlying property may abandon the property, thereby terminating the related net profits interest payable to
the Trust. XTO Energy or any other operator of the underlying properties, or any transferee thereof, may abandon any well or
property without the consent of the Trust or the Trust unitholders if they reasonably believe that the well or property can no longer produce in commercially economic quantities. This could result in the termination of the net profits interest
relating to the abandoned well or property. The net profits interests can be sold and the Trust would be terminated. The Trust will also be
terminated if it fails to generate sufficient gross proceeds. The Trust may sell the net profits interests if the holders of 80%
or more of the outstanding Trust units approve the sale or vote to terminate the Trust. The Trust will terminate if it fails to generate gross proceeds from the underlying properties of at least $1,000,000 per year over any successive two-year period. Sale of all of the net profits interests will terminate the Trust. The net proceeds of any sale must be for cash with the proceeds less any Trust administrative costs promptly distributed to the
Trust unitholders. Trust unitholders have limited voting rights and have limited ability to enforce the Trusts rights against XTO Energy or
any other operator of the underlying properties. The voting rights of a Trust unitholder are more limited than those of
stockholders of most public corporations. For example, there is no requirement for annual meetings of Trust unitholders or for an annual or other periodic re-election of the Trustee. Additionally, Trust
unitholders have no voting rights in XTO Energy or Exxon Mobil Corporation. The Trust indenture and related trust law permit the Trustee
and the Trust to sue XTO Energy or any other operator of the underlying properties to compel them to fulfill the terms of the conveyance of the net profits interests. If the Trustee does not take appropriate action to enforce provisions of the
conveyance, the recourse of the Trust unitholders would likely be limited to bringing a lawsuit against the Trustee to compel the Trustee to take specified actions. Trust unitholders probably would not be able to sue XTO Energy or any other operator
of the underlying properties. Financial information of the Trust is not prepared in accordance with U.S. GAAP. The financial statements of the Trust are prepared on a modified cash basis of accounting, which is a comprehensive basis of accounting other
than U.S. generally accepted accounting principles, or U.S. GAAP. Although this basis of accounting is permitted for royalty trusts by the Securities and Exchange Commission, the financial statements of the Trust differ from U.S. GAAP financial
statements because net profits income is not accrued in the month of production, expenses are not recognized when incurred and cash reserves may be established for certain contingencies that would not be recorded in U.S. GAAP financial statements. The limited liability of Trust unitholders is uncertain. The Trust unitholders are not protected from the liabilities of the Trust to the same extent that a shareholder would be protected from a
corporations liabilities. The structure of the Trust does not include the interposition of a limited liability entity such as a corporation or limited partnership which would provide further limited liability protection to Trust unitholders.
While the Trustee is liable for any excess liabilities incurred if the Trustee fails to ensure that such liabilities are to be satisfied only out of Trust assets, under the laws of Texas, which are  7




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unsettled on this point, a unitholder may be jointly and severally liable for any liability of the Trust if the satisfaction of such liability was not contractually limited to the assets of the
Trust and the assets of the Trust and the Trustee are not adequate to satisfy such liability. As a result, Trust unitholders may be exposed to personal liability. The Trust, however, is not liable for production costs or other liabilities of the
underlying properties. Drilling oil and natural gas wells is a high-risk activity and subjects the Trust to a variety of factors that it cannot
control. Drilling oil and natural gas wells involves numerous risks, including the risk that commercially productive oil and
natural gas reservoirs are not encountered. The presence of unanticipated pressures or irregularities in formations, miscalculations or accidents may cause drilling activities to be unsuccessful. In addition, there is often uncertainty as to the
future cost or timing of drilling, completing and operating wells. Further, development activities may be curtailed, delayed or canceled as a result of a variety of factors, including:  1.
reduced oil or natural gas prices; 2.
unexpected drilling conditions; 3.
title problems; 4.
restricted access to land for drilling or laying pipeline; 5.
pressure or irregularities in formations; 6.
equipment failures or accidents; 7.
adverse weather conditions or natural disasters; and 8.
costs of, or shortages or delays in the availability of, drilling rigs, tubular materials and equipment. While these risks do not expose the Trust to liabilities of the drilling contractor or operator of the well, they can reduce net proceeds
payable to the Trust and Trust distributions by decreasing oil and gas revenues or increasing production expense or development costs from the underlying properties. Furthermore, these risks may cause the costs of development activities on
properties underlying the 75% net profits interests to exceed the revenues therefrom, thereby reducing net proceeds payable to the Trust and Trust distributions. The underlying properties are subject to complex federal, state and local laws and regulations that could adversely affect net proceeds payable to the
Trust and Trust distributions. Extensive federal, state and local regulation of the oil and natural gas industry significantly
affects operations on the underlying properties. In particular, oil and natural gas development and production are subject to stringent environmental regulations. These regulations have increased the costs of planning, designing, drilling,
installing, operating and abandoning oil and natural gas wells and other related facilities, which costs could reduce net proceeds payable to the Trust and Trust distributions. These regulations may become more demanding in the future. See
Regulation on pp. 14-18 and Greenhouse Gas Emissions and Climate Change Regulations on p. 23-24. Cash held by the Trustee
is not insured by the Federal Deposit Insurance Corporation. Currently, cash held by the Trust reserved for the payment of accrued
liabilities and estimated future expenses and distributions to unitholders is typically held in a treasury fund that under normal market conditions invests exclusively in U.S. Treasury obligations. Although the funds underlying investments are
obligations of the U.S. government, the fund itself is not insured by the Federal Deposit Insurance Corporation. In the event that the fund becomes insolvent, the Trustee may be unable to recover any or all such cash from the insolvent fund. Any
loss of such cash may have a material adverse effect on the Trusts cash balances and any distributions to unitholders.  Item 1B.
Unresolved Staff Comments As of December 31, 2017, the Trust
did not have any unresolved Securities and Exchange Commission staff comments.  8




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Item 2.
Properties The net profits interests are the principal asset of
the Trust. The Trustee cannot acquire any other asset, with the exception of certain short-term investments as specified under Item 1, Business. The Trustee is prohibited from selling any portion of the net profits interests unless approved by
holders of at least 80% or more of the outstanding Trust units or at such time as Trust gross revenue is less than $1 million for two successive years. The net profits interests comprise:  

the 90% net profits interests which are carved from:  a)
producing royalty and overriding royalty interest properties in Texas, Oklahoma and New Mexico; and  b)
11.11% nonparticipating royalty interests in nonproducing properties located primarily in Texas and Oklahoma; and  

the 75% net profits interests which are carved from working interests in four properties in Texas and three properties in Oklahoma. All underlying royalties, underlying nonproducing royalties and underlying working interest properties are currently owned by XTO Energy or
other affiliated companies of ExxonMobil. XTO Energy may sell all or any portion of the underlying properties at any time, subject to and burdened by the net profits interests. The underlying properties include over 2,900 producing properties with established production histories in Texas, Oklahoma and New Mexico. The
average reserve-to-production index for the underlying properties as of December 31, 2017 is approximately 11 years. This index is calculated using total proved
reserves and estimated 2018 production for the underlying properties. The projected 2018 production is from proved developed producing reserves as of December 31, 2017. Based on estimated future net cash flows at
12-month average oil and gas prices, based on the
first-day-of-the-month price for each month in the period, the future net cash flows from
proved reserves of the underlying properties are approximately 45% natural gas and 55% oil. The underlying properties also include certain nonproducing properties in Texas, Oklahoma and New Mexico that are primarily mineral interests. Producing Acreage, Wells and Drilling 90% Net Profits Interests Underlying Royalties.Royalty and overriding royalty properties underlying the 90% net
profits interests represent 86% of the discounted future net cash flows from Trust proved reserves at December 31, 2017. Approximately 53% of the discounted future net cash flows from the 90% net profits interests are from gas reserves,
totaling 19.0 Bcf. Oil reserves allocated to the 90% net profits interests are primarily located in West Texas and are estimated to be 1,111,000 Bbls at December 31, 2017. The underlying royalties are royalty and overriding royalty interests primarily located in mature producing oil and gas fields. The most
significant producing region in which the underlying royalties are located is the San Juan Basin in northwestern New Mexico. The San Juan Basin royalties gas production accounted for approximately 75% of the Trusts gas sales volumes and 44% of
the net profits income for 2017. The Trusts estimated proved gas reserves from this region totaled 14.0 Bcf at December 31, 2017, or approximately 82% of Trust total gas reserves at that date. XTO Energy estimates that underlying
royalties in the San Juan Basin include more than 4,886 gross (approximately 57.5 net) wells, covering almost 60,000 gross acres. The majority of these wells are operated by BP America Production Company or Hilcorp. San Juan Basin oil and gas accumulations, inclusive of the Fruitland Coal, Pictured Cliffs, Mancos, Mesaverde, and Dakota formations, have
produced within the basin for over 90 years. Although these reservoirs have seen almost a century of development, numerous upside opportunities are still available to basin operators  9




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##### Table of Contents

via down-spacing drilling, recompletions, lateral drilling, and lease cost optimizations. Recently, operators have moved development toward the more liquid-rich portions of the basin through the
following:  1.
reduced dry gas drilling with a shift toward horizontal drilling in the more liquids-rich areas; 2.
lease optimization via compression upgrades, restimulations, and improved artificial lift; 3.
basinal work to rail crude oil out of basin to improve pricing; and 4.
stable gas pipeline infrastructure. The underlying royalties also include royalties in the
Sand Hills field of Crane County, Texas. Most of these properties are operated by major operators. The Sand Hills field was discovered in 1931 and includes production from three main intervals, the Tubb, McKnight and Judkins. Development potential
for the field includes recompletions and additional infill drilling. The underlying royalties contain approximately 282,610 gross
(approximately 36,488 net) producing acres. Well counts for the underlying royalties cannot be provided because information regarding the number of wells on royalty properties is generally not made available to royalty interest owners. Because the properties related to the 90% net profits interests are primarily royalty interests and overriding royalty interests, the net
profits income from these properties is not reduced by production or development costs, with the exception of a limited number of wells that were converted to working interest after conveyance that incur production and development costs.
Additionally, net profits income from these interests cannot be reduced by any excess costs of the 75% net profits interests. The Trust, therefore, should generally receive monthly net profits income from these interests, as determined by oil and
gas sales volumes and prices. 75% Net Profits Interests Underlying Working Interest Properties.Underlying
the 75% net profits interests are working interests in seven large, predominantly oil-producing properties in Texas and Oklahoma operated primarily by established oil companies. These properties are located in
mature fields undergoing secondary or tertiary recovery operations. Most of the oil produced from the 75% net profits interest properties is sour oil, which is sold at a discount to NYMEX sweet crude oil prices. XTO Energy is the operator of the
Hewitt Unit, which is one of the properties underlying the Oklahoma 75% net profits interests. With the exception of the Hewitt Unit, XTO Energy and ExxonMobil generally have little influence or control over operations on any of these properties. Proved reserves from the 75% net profits interests are almost entirely oil, estimated to be approximately 300,000 Bbls at year-end 2017. Proved reserves from these interests represent 14% of the discounted future net cash flows of the Trusts proved reserves at December 31, 2017. The underlying working interest properties are detailed below:  Ownership ofXTO EnergyUnit

County/State

Operator

WorkingInterest


RevenueInterestNorth Cowden

Ector/Texas

Occidental Permian, Ltd.


1.7
%


1.4
%North Central Levell and

Hockley/Texas

Apache Corporation


3.2
%


2.1
%Penwell

Ector/Texas

Cross Timbers Energy, LLC


5.2
%


4.6
%Sharon Ridge Canyon

Borden/Texas

Occidental Permian, Ltd.


4.3
%


2.8
%Hewitt

Carter/Oklahoma

XTO Energy Inc.


11.3
%


9.9
%Wildcat Jim Penn

Carter/Oklahoma

Citation Oil and Gas Corporation


8.6
%


7.5
%South Graham Deese

Carter/Oklahoma

Linn Energy, LLC


9.2
%


8.7
% The underlying working interest properties consist of 3,814 gross (2,995 net) producing acres. As of
December 31, 2017, there were 1,400 gross (70 net) productive oil wells and no wells in process of drilling on  10




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##### Table of Contents

these properties. There were no wells drilled in 2017, no wells drilled in 2016 and 12 gross (1.0 net) wells drilled in 2015. XTO Energy has advised the Trustee that it plans to drill seven
vertical wells in the Hewitt Unit during 2018. Because these underlying properties are working interests, production expense and
development costs are deducted in calculating net profits income from the 75% net profits interests. As a result, net profits income from these interests is affected by the level of maintenance and development activity on these underlying
properties. Net profits income is also dependent upon oil and gas sales volumes and prices and is subject to reduction for any prior period excess costs. Total 2017 development costs were $1,196,892, up 20% from 2016 development costs of $998,200. Development costs were higher in 2017 because of
increased development activity and costs related to non-operated Texas and Oklahoma oil properties underlying the 75% net profits interest. January and February 2018 development costs totaled approximately
$185,000, primarily incurred in fourth quarter 2017. As reported to XTO Energy by unit operators in February of each year, budgeted
development costs were $1.2 million for 2017 and $1.0 million for 2016. Actual development costs often differ from amounts budgeted because of changes in product prices and other factors that may affect the timing or selection of projects.
Also, costs are deducted in the calculation of Trust net profits income several months after they are incurred by the operator. Unit operators have reported total budgeted costs, net to the underlying properties, of approximately $1.9 million for
2018 and $1.2 million for 2019. Changes in oil or natural gas prices could impact future development plans on the underlying properties. If monthly costs exceed revenues for any conveyance, such excess costs must be recovered, with accrued interest, from future net proceeds of
that conveyance and cannot reduce net profits income from other conveyances. Remaining cumulative excess costs totaled $2,159,727 ($1,619,795 net to the Trust), including accrued interest of $0.2 million for the period ended December 31,
2017. For information regarding the effect of excess costs on Trust net profits income, see Note 7 to Financial Statements under Item 8, including the excess cost balance and accrued interest by conveyance, Financial Statements and Supplementary
Data.  11




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##### Table of Contents

Estimated Proved Reserves and Future Net Cash Flows The following are proved reserves of the underlying properties, as estimated by independent engineers, and proved reserves and future net cash
flows from proved reserves of the net profits interests, based on an allocation of these reserves, at December 31, 2017:  Underlying Properties


Net Profits InterestsProved Reserves(a)


Proved Reserves(a)(b)


Future Net Cash Flowsfrom Proved Reserves(a)(c)Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)(in thousands)





Undiscounted


Discounted90% Net Profits InterestsSan Juan Basin


22



15,547



20



13,992


$
38,945


$
20,284Other New Mexico


39



101



35



86



1,922



978Texas


993



1,941



894



1,745



46,026



22,110Oklahoma


57



1,428



51



1,198



5,763



3,223Total


1,111



19,017



1,000



17,021



92,656



46,59575% Net Profits InterestsTexas


126



63















Oklahoma


1,098



245



300



67



13,144



7,450Total


1,224



308



300



67



13,144



7,450TOTAL


2,335



19,325



1,300



17,088


$
105,800


$
54,045 (a)
Based on 12-month average oil price of $47.08 per Bbl and $3.14 per Mcf for gas, based on the first-day-of-the-month price for each month in the period.  (b)
Since the Trust has defined net profits interests, the Trust does not own a specific percentage of the oil and gas reserves. Oil and gas reserves are allocated to the net profits interests by dividing Trust net cash
inflows by 12-month average oil and gas prices. As such, reserves allocated to the Trust have been reduced to reflect recovery of the Trusts portion of applicable production and development costs, which
includes excess costs. Any conveyance where costs exceed revenues will result in zero allocated net profits interests reserves for that conveyance.  (c)
Before income taxes since future net cash flows are not subject to taxation at the trust level. Future net cash flows are discounted at an annual rate of 10%. Proved reserves at December 31, 2017 consist of the following:  Underlying Properties


Net Profits InterestsProved Reserves


Proved Reserves(in thousands)

Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)Proved developed reserves


2,335



19,325



1,300



17,088Proved undeveloped reserves














Total proved reserves


2,335



19,325



1,300



17,088 The process of estimating oil and gas reserves is complex and requires significant judgment as discussed in
Item 1A, Risk Factors, and is performed by XTO Energy. As a result, XTO Energy has developed internal policies and controls for estimating and recording reserves. XTO Energys policies regarding booking reserves require proved reserves to
be in compliance with the SEC definitions and guidance. XTO Energys policies assign responsibilities for compliance in reserves bookings to its reserve engineering group and require that reserve estimates be made by qualified reserves
estimators, as defined by the Society of Petroleum Engineers standards. All qualified reserves estimators are required to receive education covering the fundamentals of SEC proved reserves assignments.  12




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##### Table of Contents

The XTO Energy reserve engineering group reviews reserve estimates with third-party
petroleum consultants, Miller and Lents, Ltd., independent petroleum engineers. Miller and Lents, Ltd. estimated oil and gas reserves attributable to the underlying properties as of December 31, 2017, 2016, 2015 and 2014. Miller and Lents
primary technical person responsible for calculating the Trusts reserves has more than nine years of experience as a reserve engineer. The estimated reserves for the underlying properties are then used by XTO Energy to calculate the estimated
oil and gas reserves attributable to the net profits interests. Numerous uncertainties are inherent in estimating reserve volumes and values, and such estimates are subject to change as additional information becomes available. The reserves actually
recovered and the timing of production of these reserves may be substantially different from the original estimates. Reserve quantities
and revenues for the net profits interests were estimated from projections of reserves and revenues attributable to the underlying properties. Since the Trust has defined net profits interests, the Trust does not own a specific percentage of the oil
and gas reserves. Oil and gas reserves are allocated to the net profits interests by dividing Trust net cash inflows by 12-month average oil and gas prices. Oil and Natural Gas Production Trust
production is recognized in the period net profits income is received, which is the month following receipt by XTO Energy, and generally two months after the time of oil production and three months after gas production. Oil and gas sales volumes are
allocated to the net profits interests based upon a formula that considers oil and gas prices and the total amount of production expense and development costs. As such, the underlying property production volume changes may not correlate with the
Trusts net profit share of those volumes in any given period. Oil and gas production and average sales prices attributable to the
underlying properties and the net profits interests for each of the three years ended December 31 were as follows:  90% Net Profits Interests


75% Net Profits Interests


Total2017


2016


2015


2017


2016


2015


2017


2016


2015ProductionUnderlying PropertiesOilSales (Bbl)


64,268



66,487



77,221



148,474



157,801



154,836



212,742



224,288



232,057Average per day (Bbls)


176



182



212



407



431



424



583



613



636GasSales (Mcf)


1,519,441



2,043,014



1,593,141



15,475



5,678



22,897



1,534,916



2,048,692



1,616,038Average per day (Mcf)


4,163



5,582



4,365



42



16



63



4,205



5,598



4,428Net Profits InterestsOilSales (Bbls)


54,661



66,648



64,853



3,847







3,214



58,508



66,648



68,067Average per day (Bbls)


150



182



178



10







9



160



182



187GasSales (Mcf)


1,349,698



1,895,526



1,409,136



142







175



1,349,840



1,895,526



1,409,311Average per day (Mcf)


3,698



5,179



3,861















3,698



5,179



3,861Average Sales PriceOil (per Bbl)


$44.81



$40.37



$58.44



$45.34



$37.02



$49.72



$45.18



$38.02



$52.62Gas (per Mcf)


$4.08



$3.50



$4.49



$10.70



$19.61



$7.77



$4.15



$3.55



$4.54Average ProductionCost per BOE(a)


$0.08



$0.04



$0.05



$30.14



$29.47



$38.90



$9.77



$8.30



$12.34 (a)
Total average production cost per BOE includes production from the properties underlying the 90% net profits interests, which are substantially all royalty and overriding royalty interests with insignificant production
costs.  13




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##### Table of Contents

Oil and gas production by conveyance attributable to the underlying properties for each of
the three years ended December 31 were as follows:  Underlying Gas Production (Mcf)Conveyance

2017


2016


2015New Mexico royalty interest


1,122,642



1,594,530



1,008,064Oklahoma royalty interest


205,459



266,551



349,439Texas royalty interest


191,340



181,933



235,638Texas working interest


11,653



12,935



14,939Oklahoma working interest(b)


3,822



(7,257
)


7,958Total


1,534,916



2,048,692



1,616,038 (b)
Oklahoma working interest gas production for 2016 includes a one-time prior period revenue adjustment.  Underlying Oil Production (Bbls)Conveyance

2017


2016


2015New Mexico royalty interest


5,108



5,855



5,672Oklahoma royalty interest


16,483



17,686



22,075Texas royalty interest


42,677



42,946



49,474Texas working interest


51,152



56,151



60,133Oklahoma working interest


97,322



101,650



94,703Total


212,742



224,288



232,057 Nonproducing Acreage The underlying nonproducing royalties contain approximately 222,000 gross (approximately 21,000 net) acres in Texas, Oklahoma and New Mexico
which were nonproducing at the date of the Trusts creation. The Trust is entitled to 10% of oil and gas production attributable to the underlying mineral interests, but is not entitled to delay rental payments or lease bonuses. There has been
no significant development of such nonproducing acreage since the Trusts creation. Pricing and Sales Information Oil and gas are generally sold from the underlying properties at market-sensitive prices. The majority of sales from the underlying working
interest properties are to major oil and gas companies. Information about purchasers of oil and gas from royalty properties is generally not provided by operators to XTO Energy as a royalty owner, or to the Trust. Regulation Natural Gas Regulation The interstate transportation and sale for resale of natural gas is subject to federal regulation, including transportation and
storage rates charged, tariffs, and various other matters, by the Federal Energy Regulatory Commission. Federal price controls on wellhead sales of domestic natural gas terminated on January 1, 1993. While natural gas prices are currently
unregulated, Congress historically has been active in the area of natural gas regulation. On August 8, 2005, Congress enacted the Energy Policy Act of 2005. The Energy Policy Act, among other things, amended the Natural Gas Act to prohibit
market manipulation by any entity, to direct FERC to facilitate market transparency in the market for sale or transportation of physical natural gas in interstate commerce, and to significantly increase the penalties for violations of the Natural
Gas Act, the Natural Gas Policy Act of 1978, or FERC rules, regulations or orders thereunder. FERC has promulgated regulations to implement the Energy Policy Act, including enforcement rules and new annual reporting requirements for certain  14




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##### Table of Contents

sellers of natural gas. It is impossible to predict whether new legislation to regulate natural gas might be proposed, what proposals, if any, might actually be enacted by Congress or the various
state legislatures, and what effect, if any, such proposals might have on the operations of the underlying properties. Federal
Regulation of Oil Sales of crude oil, condensate and natural gas liquids are not currently regulated and are made at market prices.
The net price received from the sale of these products is affected by market transportation costs. Under rules adopted by FERC effective January 1995, interstate oil pipelines can change rates based on an inflation index, though other rate
mechanisms may be used in specific circumstances. On December 19, 2007, the President signed into law the Energy
Independence & Security Act of 2007 (PL 110-140). The EISA, among other things, prohibits market manipulation by any person in connection with the purchase or sale of crude oil, gasoline or
petroleum distillates at wholesale in contravention of such rules and regulations that the Federal Trade Commission may prescribe, directs the Federal Trade Commission to enforce the regulations, and establishes penalties for violations thereunder.
XTO Energy has advised the Trustee that it cannot predict the impact of future government regulation on any crude oil, condensate or natural gas liquids facilities, sales or transportation transactions. Environmental Regulation Companies that are engaged in the oil and gas industry are affected by federal, state and local laws regulating the discharge of materials into
the environment. Those laws may impact operations of the underlying properties. No material expenses have been incurred on the underlying properties in complying with environmental laws and regulations. XTO Energy does not expect that future
compliance will have a material adverse effect on the Trust. There is an increased focus by local, national and international regulatory
bodies on greenhouse gas (GHG) emissions and climate change. Several states have adopted climate change legislation and regulations, and various other regulatory bodies have announced their intent to regulate GHG emissions or adopt climate change
regulations. As these regulations are under development, XTO Energy is unable to predict the total impact of the potential regulations upon the operators of the underlying properties, and it is possible that operators of the underlying properties
could face increases in operating costs in order to comply with climate change or GHG emissions legislation, which costs could reduce net proceeds payable to the Trust and Trust distributions. State Regulation The
various states regulate the production and sale of oil and natural gas, including imposing requirements for obtaining drilling permits, the method of developing new fields, the spacing and operation of wells and the prevention of waste of oil and
gas resources. The rates of production may be regulated and the maximum daily production allowables from both oil and gas wells may be established on a market demand or conservation basis, or both. Federal Income Taxes For
federal income tax purposes, the Trust constitutes a fixed investment trust that is taxed as a grantor trust. A grantor trust is not subject to tax at the trust level. The unitholders are considered to own the Trusts income and principal as
though no trust were in existence. The income of the Trust is deemed to have been received or accrued by each unitholder at the time such income is received or accrued by the Trust and not when distributed by the Trust. Impairment for book purposes
will not result in a loss for tax purposes for the unitholders until the loss is recognized.  15




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##### Table of Contents

Because the Trust is a grantor trust for federal tax purposes, each unitholder is taxed
directly on his proportionate share of income, deductions and credits of the Trust consistent with each such unitholders taxable year and method of accounting and without regard to the taxable year or method of accounting employed by the
Trust. The income of the Trust consists primarily of a specified share of the net profits from the sale of oil and natural gas produced from the underlying properties. During 2017, the Trust incurred administration expenses and earned interest
income on funds held for distribution and for the cash reserve maintained for the payment of contingent and future obligations of the Trust. The net profits interests constitute economic interests in oil and gas properties for federal tax purposes. Each unitholder is
entitled to amortize the cost of the units through cost depletion over the life of the net profits interests or, if greater, through percentage depletion equal to 15 percent of gross income. Unlike cost depletion, percentage depletion is not
limited to a unitholders depletable tax basis in the units. Rather, a unitholder is entitled to a percentage depletion deduction as long as the applicable underlying properties generate gross income. Unitholders should compute both percentage
depletion and cost depletion from each property and claim the larger amount as a deduction on their income tax returns. If a taxpayer
disposes of any Section 1254 property (certain oil, gas, geothermal or other mineral property), and the adjusted basis of such property includes adjustments for depletion deductions under Section 611 of the Internal Revenue
Code (the Code), the taxpayer generally must recapture the amount deducted for depletion as ordinary income (to the extent of gain realized on such disposition). This depletion recapture rule applies to any disposition of property that
was placed in service by the taxpayer after December 31, 1986. Detailed rules set forth in Sections 1.1254-1 through 1.1254-6 of the U.S. Treasury Regulations
govern dispositions of property after March 13, 1995. The Internal Revenue Service likely will take the position that a unitholder must recapture depletion upon the disposition of a unit. Interest and net profits income attributable to ownership of units and any gain on the sale thereof are considered portfolio income, and not
income from a passive activity, to the extent a unitholder acquires and holds units as an investment and not in the ordinary course of a trade or business. Therefore, interest and net profits income attributable to ownership of units
generally may not be offset by losses from any passive activities. Under the recently enacted 2017 Tax Cuts and Jobs Act (the
TCJA), for tax years beginning after December 31, 2017 and before January 1, 2026, the highest marginal U.S. federal income tax rate applicable to ordinary income of individuals is 37%, and the highest marginal U.S. federal
income tax rate applicable to long-term capital gains (generally, gains from the sale or exchange of certain investment assets held for more than one year) and qualified dividends of individuals is 20%. Under TCJA, for such tax years, personal
exemptions and miscellaneous itemized deductions are not allowed. For such tax years, the U.S. federal income tax rate applicable to corporations is 21%, and such rate applies to both ordinary income and capital gains. Individuals may also incur expenses in connection with the acquisition or maintenance of Trust units. For tax years beginning before
January 1, 2018, these expenses, which are different from a unitholders share of the Trusts administrative expenses discussed above, may be deductible as miscellaneous itemized deductions only to the extent that such
expenses exceed 2 percent of the individuals adjusted gross income. Under the TCJA, for tax years beginning after December 31, 2017 and before January 1, 2026, miscellaneous itemized deductions are not allowed. For tax years beginning before January 1, 2018, the highest marginal U.S. federal income tax rate applicable to ordinary income of
individuals is 39.6%, and the highest marginal U.S. federal income tax rate applicable to long-term capital gains and qualified dividends of individuals is 20%. For such pre-2018 tax years, such marginal tax
rates may be effectively increased by up to 1.2% due to the phaseout of personal exemptions and the limitations on itemized deductions. For such pre-2018 tax years, the highest marginal U.S. federal income tax
rate applicable to corporations is 35%, and such rate applies to both ordinary income and capital gains.  16




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##### Table of Contents

Section 1411 of the Code imposes a 3.8% Medicare tax on certain investment income
earned by individuals, estates, and trusts. For these purposes, investment income generally will include a unitholders allocable share of the Trusts interest and royalty income plus the gain recognized from a sale of Trust units. In the
case of an individual, the tax is imposed on the lesser of (i) the individuals net investment income from all investments, or (ii) the amount by which the individuals modified adjusted gross income exceeds specified threshold
levels depending on such individuals federal income tax filing status. In the case of an estate or trust, the tax is imposed on the lesser of (i) undistributed net investment income, or (ii) the excess adjusted gross income over the
dollar amount at which the highest income tax bracket applicable to an estate or trust begins. The difference between the per-unit taxable income for any period and the per-unit cash distributions, if any, reported for such period is attributable to (i) items that reduce cash distributions
but are not currently deductible, such as an increase in the cash reserve maintained by the Trust for the payment of future expenditures; (ii) the current deduction of expenses that are paid with amounts previously reserved; (iii) items
that increase cash distributions but do not constitute taxable income, such as a decrease in the cash reserve maintained by the Trust and/or a return of capital; and (iv) items that constitute taxable income due to the recovery of prior period
expense adjustments. Because of these types of items and when the Trustee elects to reserve amounts from monthly distributions to maintain an administrative expense reserve, the taxable income per period frequently differs from the actual amount
distributed to unitholders. Pursuant to the Foreign Account Tax Compliance Act (commonly referred to as FATCA), distributions
from the Trust to foreign financial institutions and certain other non-financial foreign entities may be subject to U.S. withholding taxes. Specifically, certain withholdable
payments (including certain royalties, interest and other gains or income from U.S. sources) made to a foreign financial institution or non-financial foreign entity will generally be subject to the
withholding tax unless the foreign financial institution or non-financial foreign entity complies with certain information reporting, withholding, identification, certification and related requirements imposed
by FATCA. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules. The Treasury Department issued guidance providing that the FATCA withholding rules described above generally apply to qualifying payments made
after June 30, 2014. Foreign unitholders are encouraged to consult their own tax advisors regarding the possible implications of these withholding provisions on their investment in Trust units. Some Trust units are held by middlemen, as such term is broadly defined in U.S. Treasury Regulations (and includes custodians, nominees,
certain joint owners, and brokers holding an interest for a customer in street name, collectively referred to herein as middlemen). Therefore, the Trustee considers the Trust to be a non-mortgage
widely held fixed investment trust (WHFIT) for U.S. federal income tax purposes. Simmons Bank, EIN: 71-0162300, Post Office Box 962020, Fort Worth, Texas, 76162-2020, telephone number 1-855-588-7839, email address Trustee@crt-crosstimbers.com, is the representative of the Trust
that will provide tax information in accordance with applicable U.S. Treasury Regulations governing the information reporting requirements of the Trust as a WHFIT. Tax information is also posted by the Trustee at
www.crt-crosstimbers.com. Notwithstanding the foregoing, the middlemen holding Trust units on behalf of unitholders, and not the Trustee of the Trust, are solely responsible for complying with the
information reporting requirements under the U.S. Treasury Regulations with respect to such Trust units, including the issuance of IRS Forms 1099 and certain written tax statements. Unitholders whose Trust units are held by middlemen should consult
with such middlemen regarding the information that will be reported to them by the middlemen with respect to the Trust units. Unitholders
should consult their tax advisors regarding trust tax compliance matters.  17




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##### Table of Contents

State Taxes All revenues from the Trust are from sources within Texas, Oklahoma or New Mexico. Because it distributes all of its net income to unitholders,
the Trust has not been taxed at the trust level in New Mexico or Oklahoma. While the Trust has not owed tax, the Trustee is required to file an Oklahoma income tax return reflecting the income and deductions of the Trust attributable to properties
located in that state, along with a schedule that includes information regarding distributions to unitholders. Oklahoma and New Mexico tax the income of nonresidents from real property located within those states, and the Trust has been advised by
counsel that such states will tax nonresidents on income from the net profits interests located in those states. Oklahoma and New Mexico also impose a corporate income tax that may apply to unitholders organized as corporations (subject to certain
exceptions for S corporations and limited liability companies, depending on their treatment for federal tax purposes). Texas imposes a
franchise tax at a rate of .75% on gross revenues less certain deductions, as specifically set forth in the Texas franchise tax statutes. Entities subject to tax generally include trusts and most other types of entities that provide limited
liability protection, unless otherwise exempt. Trusts that receive at least 90% of their federal gross income from certain passive sources, including royalties from mineral properties and other non-operated
mineral interest income, and do not receive more than 10% of their income from operating an active trade or business, generally are exempt from the Texas franchise tax as passive entities. The Trust has been and expects to continue to be
exempt from Texas franchise tax as a passive entity. Because the Trust should be exempt from Texas franchise tax at the trust level as a passive entity, each unitholder that is a taxable entity under the Texas franchise tax will generally be
required to include its Texas portion of trust revenues in its own Texas franchise tax computation. This revenue is sourced to Texas under provisions of the Texas Administrative Code providing that such income is sourced according to the principal
place of business of the Trust, which is Texas. Each unitholder should consult his or her own tax advisor regarding state income tax
requirements, if any, applicable to such persons ownership of Trust units. State Tax Withholding Several states have enacted legislation requiring state income tax withholding from payments to nonresident recipients of oil and gas proceeds.
After consultation with its tax counsel, the Trustee believes that it is not required to withhold on payments made to the unitholders. However, regulations are subject to change by the various states, which could change this conclusion. Should
amounts be withheld on payments made to the Trust or the unitholders, distributions to the unitholders would be reduced by the required amount, subject to the filing of a claim for refund by the Trust or unitholders for such amount. Other Regulation The
petroleum industry is also subject to compliance with various other federal, state and local regulations and laws, including, but not limited to, regulations and laws relating to environmental protection, occupational safety, resource conservation
and equal employment opportunity. XTO Energy has advised the Trustee that it does not believe that compliance with these laws will have any material adverse effect upon the unitholders.  Item 3.
Legal Proceedings Certain of the underlying properties are
involved in various lawsuits and certain governmental proceedings arising in the ordinary course of business. XTO Energy has advised the Trustee that it does not believe that the ultimate resolution of these claims will have a material effect on
Trust annual distributable income, financial position or liquidity.  Item 4.
Mine Safety Disclosures Not Applicable.  18




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##### Table of Contents

PART II  Item 5.
Market for Units of the Trust, Related Unitholder Matters and Trust Purchases of Units Units of Beneficial Interest The units of
beneficial interest in the Trust are listed and traded on the New York Stock Exchange under the symbol CRT. The following are the high and low intraday unit sales prices and total cash distributions per unit paid by the Trust during each
quarter of 2017 and 2016:  Sales Price


Distributionsper UnitQuarter

High


Low2017First

$
19.00


$
14.10


$
0.230570Second


16.60



14.47



0.253592Third


15.71



14.10



0.254405Fourth


15.47



14.10



0.270398$
1.0089652016First

$
16.46


$
12.00


$
0.363497Second


18.20



14.50



0.162530Third


20.59



17.65



0.216652Fourth


19.80



16.11



0.318121$
1.060800 At December 31, 2017, there were 6,000,000 units outstanding and approximately 200 unitholders of record;
5,896,091 of these units were held by depository institutions. The Trust has no equity compensation plans, nor has it purchased any units
during the period covered by this report. See Item 1. Business for a description of the Trustees obligations to make
monthly distributions and how the monthly distribution amount is determined under the indenture.  Item 6.
Selected Financial Data  Year Ended December 312017


2016


2015


2014


2013Net Profits Income

$
6,621,337


$
7,541,706


$
8,884,319


$
16,449,036


$
14,290,356Distributable Income


6,053,790



6,364,800



8,128,668



15,945,300



13,887,594Distributable Income per Unit


1.008965



1.060800



1.354778



2.657550



2.314599Distributions per Unit


1.008965



1.060800



1.354778



2.657550



2.314599Total Assets at Year-End


10,782,124



11,448,234



11,511,940



12,272,598



12,935,109  19




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##### Table of Contents

Item 7.
TrusteesDiscussion and Analysis of Financial Condition and Results of Operations Calculation of Net Profits Income The
following is a summary of the calculation of net profits income received by the Trust:  Year Ended December 31(a)


Quarter EndedDecember 31(a)2017


2016


2015


2017


2016Sales VolumesOil (Bbls)(b)Underlying properties


212,742



224,288



232,057



57,561



53,062Average per day


583



613



636



626



577Net profits interests


58,508



66,648



68,067



18,650



16,729Gas (Mcf)(b)Underlying properties


1,534,916



2,048,692



1,616,038



342,082



509,725Average per day


4,205



5,598



4,428



3,718



5,540Net profits interests


1,349,840



1,895,526



1,409,311



300,566



486,262Average Sales PriceOil (per Bbl)


$45.18



$38.02



$52.62



$44.11



$42.16Gas (per Mcf)


$4.15



$3.55



$4.54



$4.12



$3.45RevenuesOil sales

$
9,611,560


$
8,526,335


$
12,211,006


$
2,538,987


$
2,237,209Gas sales


6,370,642



7,268,081



7,337,579



1,409,678



1,757,270Total Revenues


15,982,202



15,794,416



19,548,585



3,948,665



3,994,479CostsTaxes, transportation and other


2,356,681



2,331,326



2,714,689



513,110



563,628Production expense(c)


4,578,088



4,462,800



6,189,352



1,248,293



1,110,056Development costs


1,196,892



998,200



2,697,664



129,096



237,045Excess costs(d)


459,235



(377,583
)


(1,972,100
)


146,831



(61,794
)Total Costs


8,590,896



7,414,743



9,629,605



2,037,330



1,848,935Net Proceeds

$
7,391,306


$
8,379,673


$
9,918,980


$
1,911,335


$
2,145,544Net Profits Income

$
6,621,337


$
7,541,706


$
8,884,319


$
1,689,363


$
1,930,990 (a)
Because of the interval between time of production and receipt of net profits income by the Trust, oil and gas sales for the year ended December 31 generally relate to oil production from November through October
and gas production from October through September, while oil and gas sales for the quarter ended December 31 generally relate to oil production from August through October and gas production from July through September.  (b)
Oil and gas sales volumes are allocated to the net profits interests by dividing Trust net cash inflows by average sales prices. As oil and gas prices change, the Trusts allocated production volumes are impacted
as the quantity of production necessary to cover expenses changes inversely with price. As such, the underlying property production volume changes may not correlate with the Trusts allocated production volumes in any given period. Therefore,
comparative discussion of oil and gas sales volumes is based on the underlying properties.  (c)
Production expense is primarily from seven working interest properties in the 75% net profits interest. Six of these properties are not operated by XTO Energy or ExxonMobil. Production expense includes an overhead
charge which is deducted and retained by the operator. As of December 31, 2017, this charge was $39,245 per month (including a monthly overhead charge of $5,607 which XTO Energy deducts as operator of the Hewitt Unit) and is subject to
adjustment each May based on an oil and gas industry index.  (d)
See Note 7 to Financial Statements under Item 8, Financial Statements and Supplementary Data.  20




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##### Table of Contents

Results of Operations Years Ended December 31, 2017, 2016 and 2015 Net profits income for 2017 was $6,621,337 as compared with $7,541,706 for 2016 and $8,884,319 for 2015. The 12% decrease in net profits income
from 2016 to 2017 was primarily because of decreased oil and gas production ($2.3 million), excess costs on the Texas and Oklahoma working interest properties in 2016 ($0.6 million), higher development costs ($0.1 million), increased production
expense ($0.1 million), and increased taxes ($0.1 million), partially offset by higher oil and gas prices ($2.3 million). The 15% decrease in net profits income from 2015 to 2016 was primarily because of lower oil and gas prices ($4.0 million),
excess costs on the Texas and Oklahoma working interest properties in 2015 ($1.2 million) and decreased oil production ($0.3 million), partially offset by decreased production expenses ($1.3 million), lower development costs
($1.3 million), increased gas production ($1.2 million) and decreased taxes, transportation and other costs ($0.4 million). During 2017, 2016 and 2015, 62%, 66% and 56%, respectively, of net profits income was derived from gas sales. Trust administration expense was $575,144 in 2017 as compared to $475,015 in 2016 and $480,694 in 2015. Cash reserve activity was $0 in 2017
as compared to $725,000 in 2016 and $275,000 in 2015, which the Trustee reserved for administrative expenses. As of December 31, 2017, the reserve is fully funded at $1,000,000. Interest income was $7,597 in 2017, $23,109 in 2016 and $43 in
2015. Interest income in 2016 included $22,071 related to a prior period expense adjustment. Other changes in interest income are attributable to fluctuations in net profits income and interest rates. Net profits income is recorded when received by the Trust, which is the month following receipt by XTO Energy, and generally two months after
oil production and three months after gas production. Net profits income is generally affected by three major factors:  1.
oil and gas sales volumes; 2.
oil and gas sales prices; and 3.
costs deducted in the calculation of net profits income. Volumes Oil.    Underlying oil sales volumes decreased 5% from 2016 to 2017 compared to a 3% decrease from 2015 to 2016. Oil
sales volumes in 2017 decreased from 2016 primarily because of natural production decline. Oil sales volumes in 2016 decreased from 2015 primarily because of natural production decline, partially offset by the timing of cash receipts. Gas.    Underlying gas sales volumes decreased 25% from 2016 to 2017 compared to a 27% increase from 2015 to 2016.
Gas sales volumes in 2017 decreased from 2016 primarily because of the timing of cash receipts and natural production decline. Gas sales volumes in 2016 increased from 2015 primarily because of the timing of cash receipts related to purchaser
payments covering production back to 2013, partially offset by natural production decline. The estimated rate of natural production
decline on the underlying oil and gas properties is approximately 6% to 8% a year. Prices Oil.    The average oil price for 2017 was $45.18 per Bbl, a 19% increase from the 2016 average oil price of $38.02,
which was a 28% decrease from the 2015 average oil price of $52.62. Oil prices are expected to remain volatile. The average NYMEX price for November 2017 through January 2018 was $59.50 per Bbl. At March 1, 2018, the average NYMEX oil price for
the following 12 months was $59.05 per Bbl.  21




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##### Table of Contents

Gas.    The 2017 average gas price was $4.15 per Mcf, a 17%
increase from the 2016 average gas price of $3.55, which was 22% lower than the 2015 average price of $4.54. Excluding the impact of the prior period production payments received in 2016, the adjusted gas price was $2.97 per Mcf. Natural gas prices
are affected by natural gas liquids prices, the level of North American production, weather, crude oil prices, the U.S. economy, storage levels and import levels of liquefied natural gas. Natural gas prices are expected to remain volatile. The
average NYMEX price for fourth quarter 2017 was $3.00 per MMBtu. At March 1, 2018, the average NYMEX gas price for the following 12 months was $2.86 per MMBtu. Costs Because properties
underlying the 90% net profits interests are primarily royalty and overriding royalty interests, the calculation of net profits income from these interests includes deductions for production and property taxes, legal costs, and marketing and
transportation charges. In addition to these costs, the calculation of net profits income from the 75% net profits interests includes deductions for production expense and development costs since the related underlying properties are working
interests. Net profits income is calculated monthly for each of the five conveyances under which the net profits interests were conveyed to the Trust. If monthly costs exceed revenues for any conveyance, such excess costs must be recovered, with
accrued interest, from future net proceeds of that conveyance and cannot reduce net profits income from other conveyances. Costs have never exceeded revenues from 90% net profits interests, nor are they expected to in the future. For further
information on excess costs, see Note 7 to Financial Statements under Item 8, Financial Statements and Supplementary Data. Total costs
deducted in the calculation of net profits income were $8.6 million in 2017, $7.4 million in 2016 and $9.6 million in 2015. The 16% increase in costs from 2016 to 2017 is attributable to excess costs on the Texas and Oklahoma working
interest properties in 2016 and increased development activities and costs on non-operated Texas and Oklahoma oil properties underlying the 75% net profits interest, partially offset by lower oil and gas
production taxes related to decreased oil and gas production. The 23% decrease in costs from 2015 to 2016 is attributable to decreased production expense related to decreased outside operated costs, lower development costs related to decreased
development activities and costs on non-operated Texas and Oklahoma oil properties underlying the 75% net profits interest, decreased oil and gas production taxes related to lower oil and gas revenues,
partially offset by excess costs on the Texas and Oklahoma working interest properties in 2015 and increased other deductions related to increased gas production. Unit operators of the properties underlying the 75% net profits interests have reported total budgeted development costs, net to the
underlying properties, of approximately $1.9 million for 2018 and $1.2 million for 2019, as compared to budgeted development costs of $1.2 million and actual development costs of $1.2 million for 2017. Actual development costs often differ from
amounts budgeted because of changes in product prices and other factors that may affect the timing or selection of projects. Changes in oil or natural gas prices could impact future development plans on the underlying properties. Fourth Quarter 2017 and 2016 During the
quarter ended December 31, 2017, the Trust received net profits income totaling $1,689,363, compared with fourth quarter 2016 net profits income of $1,930,990. This 13% decrease is primarily attributable to decreased gas production ($0.6
million), excess costs on the Texas and Oklahoma working interest properties in 2016 ($0.2 million), and higher production expenses ($0.1 million), partially offset by higher oil and gas prices ($0.4 million), increased oil production ($0.2
million), and decreased development costs ($0.1 million).  22




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##### Table of Contents

Administration expense was $69,764 and Trust interest income was $2,789, resulting in fourth
quarter 2017 distributable income of $1,622,388, or $0.270398 per unit. Distributable income for fourth quarter 2016 was $1,908,726, or $0.318121 per unit. Distributions to unitholders for the quarter ended December 31, 2017 were:  Record Date

Payment Date

Per UnitOctober 31, 2017

November 14, 2017

$
0.099021November 30, 2017

December 14, 2017


0.092912December 29, 2017

January 16, 2018


0.078465$
0.270398 Volumes Fourth quarter 2017 underlying oil sales volumes were 57,561 Bbls, or 8% higher than 2016 levels primarily due to the timing of cash receipts,
partially offset by natural production decline. Underlying gas sales volumes for fourth quarter 2017 were 342,082 Mcf, 33% lower than 2016 levels due to the timing of cash receipts and natural production decline. Prices The average fourth quarter
2017 oil price was $44.11 per Bbl, 5% higher than the fourth quarter 2016 average price of $42.16. The average fourth quarter 2017 gas price was $4.12 per Mcf, 19% higher than the fourth quarter 2016 average price of $3.45. For further information
about oil and gas prices, see Years Ended December 31, 2017, 2016 and 2015  Prices above. Costs Costs deducted in the calculation of fourth quarter 2017 net profits income increased $188,395, or 10%, from fourth quarter 2016. This increase
was primarily attributable to excess costs on the Texas and Oklahoma working interest properties in 2016, increased production expense related to increased outside operated costs and increased property taxes, partially offset by lower development
costs related to decreased development activities and costs on non-operated Texas and Oklahoma oil properties underlying the 75% net profits interests, decreased oil and gas production taxes related to lower
oil and gas revenues. For further information about development and excess costs, see Years Ended December 31, 2017, 2016 and 2015  Costs above. Liquidity and Capital Resources The
Trusts only cash requirement is the monthly distribution of its income to unitholders, which is funded by the monthly receipt of net profits income after payment of Trust administration expenses. The Trust is not liable for any production
costs or liabilities attributable to the underlying properties. If at any time the Trust receives net profits income in excess of the amount due, the Trust is not obligated to return such overpayment, but future net profits income payable to the
Trust will be reduced by the overpayment, plus interest at the prime rate. The Trust may borrow funds required to pay Trust liabilities if fully repaid prior to further distributions to unitholders. The Trust does not have any transactions, arrangements or other relationships with unconsolidated entities or persons that could materially
affect the Trusts liquidity or the availability of capital resources. Greenhouse Gas Emissions and Climate Change Regulations There is an increased focus by local, national and international regulatory bodies on greenhouse gas (GHG) emissions and climate change.
Several states have adopted climate change legislation and regulations, and  23




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##### Table of Contents

various other regulatory bodies have announced their intent to regulate GHG emissions or adopt climate change regulations. The climate accord reached at the Conference of the Parties (COP21) in
Paris set many new goals, and while many related policies are still emerging, XTO Energy has informed the Trustee that it continues to anticipate that such policies will increase the cost of carbon dioxide emissions over time. As these regulations
are under development, XTO Energy is unable to predict the total impact of the potential regulations upon the operators of the underlying properties, and it is possible that the operators of the underlying properties could face increases in
operating costs in order to comply with climate change or GHG emissions legislation, which costs could reduce net proceeds payable to the Trust and Trust distributions. Off-Balance Sheet Arrangements The Trust has no off-balance sheet financing arrangements. The Trust has not guaranteed the debt of any
other party, nor does the Trust have any other arrangements or relationships with other entities that could potentially result in unconsolidated debt, losses or contingent obligations. Contractual Obligations As shown below,
the Trust had no obligations and commitments to make future contractual payments as of December 31, 2017, other than the December distribution payable to unitholders in January 2018, as shown in the statement of assets, liabilities and trust
corpus.  Payments due by PeriodTotal


Less than1 Year


1 - 3 Years


3 - 5 Years


More than5 YearsDistribution payable to unitholders

$
470,790


$
470,790


$



$



$
 Related Party Transactions The underlying properties are currently owned by XTO Energy. XTO Energy deducts an overhead charge from monthly net proceeds as reimbursement
for costs associated with monitoring the 75% net profits interests. As of December 31, 2017, this monthly charge was $39,245 ($29,434 net to the Trust). Included in this monthly overhead charge is a charge XTO Energy deducts as operator of the
Hewitt Unit. As of December 31, 2017, monthly overhead attributable to the Hewitt Unit was $5,607 ($4,205 net to the Trust). These overhead charges are subject to annual adjustment based on an oil and gas industry index. For further information
regarding the Trusts relationship with XTO Energy, see Note 5 to Financial Statements under Item 8, Financial Statements and Supplementary Data. On June 25, 2010, XTO Energy became a wholly owned subsidiary of Exxon Mobil Corporation. Critical Accounting Policies The
financial statements of the Trust are significantly affected by its basis of accounting and estimates related to its oil and gas properties and proved reserves, as summarized below. Basis of Accounting The
Trusts financial statements are prepared on a modified cash basis, which is a comprehensive basis of accounting other than U.S. generally accepted accounting principles. This method of accounting is consistent with reporting of taxable income
to Trust unitholders. The most significant differences between the Trusts financial statements and those prepared in accordance with U.S. generally accepted accounting principles are:  1.
net profits income is recognized in the month received rather than accrued in the month of production;  2.
expenses are recognized when paid rather than when incurred; and  24




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##### Table of Contents

3.
cash reserves may be established by the Trustee for certain contingencies that would not be recorded under U.S. generally accepted accounting principles. This comprehensive basis of accounting other than U.S. generally accepted accounting principles corresponds to the accounting permitted for
royalty trusts by the U.S. Securities and Exchange Commission, as specified by Staff Accounting Bulletin Topic 12:E, Financial Statements of Royalty Trusts. For further information regarding the Trusts basis of accounting, see Note 2 to
Financial Statements under Item 8, Financial Statements and Supplementary Data. All amounts included in the Trusts financial
statements are based on cash amounts received or disbursed, or on the carrying value of the net profits interests, which was derived from the historical cost of the interests at the date of their transfer from XTO Energy, less accumulated
amortization to date. Accordingly, there are no fair value estimates included in the financial statements based on either exchange or non-exchange trade values. Impairment The Trustee
reviews the Trusts net profits interests (NPI) in oil and gas properties for impairment whenever events or circumstances indicate that the carrying value of the NPI may not be recoverable. In general, the Trustee does not view temporarily low prices as an indication of impairment. The markets for crude oil and natural gas have a
history of significant price volatility and though prices will occasionally drop significantly, industry prices over the long term will continue to be driven by market supply and demand. If events and circumstances indicated that the carrying value
may not be recoverable, the Trustee would use the estimated undiscounted future net cash flows from the NPI to evaluate the recoverability of the Trust assets. If the undiscounted future net cash flows from the NPI are less than the NPI carrying
value, the Trust would recognize an impairment loss for the difference between the NPI carrying value and the estimated fair value of the NPI. The determination as to whether the NPI is impaired requires a significant amount of judgment by the Trustee and is based on the best
information available to the Trustee at the time of the evaluation. There was no impairment of the assets as of December 31, 2017. Oil and Gas Reserves The
proved oil and gas reserves for the underlying properties are estimated by independent petroleum engineers. The estimated reserves for the underlying properties are then used by XTO Energy to calculate the estimated oil and gas reserves attributable
to the net profits interests. Reserve engineering is a subjective process that is dependent upon the quality of available data and the interpretation thereof. Estimates by different engineers often vary, sometimes significantly. In addition,
physical factors such as the results of drilling, testing and production subsequent to the date of an estimate, as well as economic factors such as changes in product prices, may justify revision of such estimates. Because proved reserves are
required to be estimated using 12-month average prices, based on the
first-day-of-the-month price for each month in the period, estimated reserve quantities
can be significantly impacted by changes in product prices. Accordingly, oil and gas quantities ultimately recovered and the timing of production may be substantially different from original estimates. The standardized measure of discounted future net cash flows and changes in such cash flows, as reported in Note 8 to Financial Statements
under Item 8, Financial Statements and Supplementary Data, is prepared using assumptions required by the Financial Accounting Standards Board and the Securities and Exchange Commission. Such assumptions include using 12-month average oil and gas prices, based on the
first-day-of-the-month price for each month in the period, and year end costs for
estimated future development and production expenditures, including recovery of cumulative excess costs remaining at year end. Discounted future net cash flows are calculated using a 10% rate. Changes in any of these assumptions, including  25




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##### Table of Contents

consideration of other factors, could have a significant impact on the standardized measure. Accordingly, the standardized measure does not represent XTO Energys or the Trustees
estimated current market value of proved reserves. Forward-Looking Statements Certain information included in this annual report and other materials filed, or to be filed, by the Trust with the Securities and Exchange
Commission (as well as information included in oral statements or other written statements made or to be made by XTO Energy or the Trustee) contain forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of
1934, as amended, and Section 27A of the Securities Act of 1933, as amended, relating to the Trust, operations of the underlying properties and the oil and gas industry. Such forward-looking statements may concern, among other things,
development activities, future development plans, increased density drilling, reserve-to-production ratios, future production, future net cash flows, maintenance
projects, development, production and other costs, oil and gas prices, pricing differentials, proved reserves, production levels, litigation, political and regulatory matters and competition. Such forward-looking statements are based on XTO
Energys current plans, expectations, assumptions, projections and estimates and are identified by words such as expects, intends, plans, projects, anticipates, predicts,
believes, goals, estimates, should, could, and similar words that convey the uncertainty of future events. These statements are not guarantees of future performance and involve certain
risks, uncertainties and assumptions that are difficult to predict. Therefore, actual financial and operational results may differ materially from expectations, estimates or assumptions expressed in, implied in, or forecasted in such forward-looking
statements. Some of the risk factors that could cause actual results to differ materially are explained in Item 1A, Risk Factors.  Item 7A.
Quantitative and Qualitative Disclosures about Market Risk The
only assets of and sources of income to the Trust are the net profits interests, which generally entitle the Trust to receive a share of the net profits from oil and gas production from the underlying properties. Consequently, the Trust is exposed
to market risk from fluctuations in oil and gas prices. A significant decline in oil or natural gas prices could have a material adverse effect on the amount of oil and natural gas that is economic to produce, Trust net profits and proved reserves
attributable to the Trusts interests. The Trust is a passive entity and, other than the Trusts ability to periodically borrow money as necessary to pay expenses, liabilities and obligations of the Trust that cannot be paid out of cash
held by the Trust, the Trust is prohibited from engaging in borrowing transactions. The amount of any such borrowings is unlikely to be material to the Trust. In addition, the Trustee is prohibited by the Trust indenture from engaging in any
business activity or causing the Trust to enter into any investments other than investing cash on hand in specific short-term cash investments. Therefore, the Trust cannot hold any derivative financial instruments. As a result of the limited nature
of its borrowing and investing activities, the Trust is not subject to any material interest rate market risk. The Trust does not engage in transactions in foreign currencies which could expose the Trust to any foreign currency related market risk.  Item 8.
Financial Statements and Supplementary Data  PageReport of Independent Registered Public Accounting Firm


27Statements of Assets, Liabilities and Trust Corpus


29Statements of Distributable Income


29Statements of Changes in Trust Corpus


29Notes to Financial Statements


30 All financial statement schedules are omitted as they are inapplicable or the required information has been
included in the consolidated financial statements or notes thereto.  26




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##### Table of Contents

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM To the Unitholders of Cross Timbers Royalty Trust and Simmons Bank, as Trustee Opinions on the Financial
Statements and Internal Control over Financial Reporting We have audited the accompanying statements of assets, liabilities and
trust corpus of Cross Timbers Royalty Trust (the Trust) as of December 31, 2017 and 2016, and the related statements of distributable income and of changes in trust corpus for each of the three years in the period ended
December 31, 2017, including the related notes (collectively referred to as the financial statements). We also have audited the Trusts internal control over financial reporting as of December 31, 2017, based on criteria
established in Internal ControlIntegrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). In our opinion, the financial statements referred to above present fairly, in all material respects, the assets, liabilities and trust corpus
of the Trust as of December 31, 2017 and 2016,and its distributable income and its changes in trust corpus for each of the three years in the period ended December 31, 2017 in conformity with the modified cash basis of accounting
described in Note 2. Also in our opinion, the Trust maintained, in all material respects, effective internal control over financial reporting as of December 31, 2017, based on criteria established in Internal ControlIntegrated
Framework (2013) issued by the COSO. Basis for Opinions The Trusts management is responsible for these financial statements, for maintaining effective internal control over financial reporting,
and for its assessment of the effectiveness of internal control over financial reporting, included in the Trustees Report on Internal Control Over Financial Reporting, appearing under Item 9A. Our responsibility is to express opinions on
the Trusts financial statements and on the Trusts internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States)
(PCAOB) and are required to be independent with respect to the Trust in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain
reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects. Our audits of the financial statements included performing procedures to assess the risks of material misstatement of the financial
statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also
included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. Our audit of internal control over financial reporting included obtaining an
understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also
included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions. Basis of Accounting As described
in Note 2, these financial statements were prepared on the modified cash basis of accounting, which is a comprehensive basis of accounting other than accounting principles generally accepted in the United States of America.  27




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##### Table of Contents

Definition and Limitations of Internal Control over Financial Reporting A trusts internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of
financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A trusts internal control over financial reporting includes those policies and procedures that
(i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the trust; (ii) provide reasonable assurance that transactions are recorded as necessary
to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the trust are being made only in accordance with authorizations of management and the Trustee; and
(iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the trusts assets that could have a material effect on the financial statements. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of
any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. /s/ PricewaterhouseCoopers LLP Dallas, Texas March 12, 2018 We have served as the Trusts auditor
since 2011.  28




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST STATEMENTS OF ASSETS, LIABILITIES AND TRUST CORPUS  December 312017


2016AssetsCash and short-term investments

$
1,469,830


$
1,544,252Interest to be received


960



182Net profits interests in oil and gas propertiesnet (Notes 1 and 2)


9,311,334



9,903,800$
10,782,124


$
11,448,234Liabilities and Trust CorpusDistribution payable to unitholders

$
470,790


$
544,434Expense reserve(a)


1,000,000



1,000,000Trust corpus (6,000,000 units of beneficial interest authorized and outstanding)


9,311,334



9,903,800$
10,782,124


$
11,448,234 (a)
Expense reserve allows the Trustee to pay its obligations should it be unable to pay them out of the net profits income. The reserve is currently fully funded at $1,000,000. STATEMENTS OF DISTRIBUTABLE INCOME  Year Ended December 312017


2016


2015Net profits income

$
6,621,337


$
7,541,706


$
8,884,319Interest income(a)


7,597



23,109



43Total income


6,628,934



7,564,815



8,884,362Administration expense


575,144



475,015



480,694Cash reserves withheld for Trust expenses






725,000



275,000Distributable income

$
6,053,790


$
6,364,800


$
8,128,668Distributable income per unit (6,000,000 units)

$
1.008965


$
1.060800


$
1.354778 (a)
Interest income for the period ended December 31, 2016 includes $22,071 related to a prior period expense adjustment. STATEMENTS OF CHANGES IN TRUST CORPUS  Year Ended December 312017


2016


2015Trust corpus, beginning of year

$
9,903,800


$
10,542,236


$
10,994,298Amortization of net profits interests


(592,466
)


(638,436
)


(452,062
)Distributable income


6,053,790



6,364,800



8,128,668Distributions declared


(6,053,790
)


(6,364,800
)


(8,128,668
)Trust corpus, end of year

$
9,311,334


$
9,903,800


$
10,542,236 See accompanying notes to financial statements.  29




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS 1. Trust Organization and Provisions Cross Timbers Royalty Trust (the Trust) was created on February 12, 1991 by predecessors of XTO Energy Inc., when the
following net profits interests were conveyed under five separate conveyances to the Trust effective October 1, 1990, in exchange for 6,000,000 units of beneficial interest in the Trust:  1.
90% net profits interests in certain producing and nonproducing royalty and overriding royalty interest properties in Texas, Oklahoma and New Mexico; and  2.
75% net profits interests in certain working interest properties in Texas and Oklahoma. The
underlying properties from which the net profits interests were carved are currently owned by XTO Energy (Note 5). The Trusts initial public offering was in February 1992. Simmons Bank is the Trustee of the Trust. The Trust indenture provides, among other provisions, that:  1.
the Trust may not engage in any business activity or acquire any assets other than the net profits interests and specific short-term cash investments;  2.
the Trust may not dispose of all or part of the net profits interests unless approved by holders of 80% or more of the outstanding Trust units, or upon Trust termination, and any sale must be for cash with the proceeds
promptly distributed to the unitholders on the next declared distribution;  3.
the Trustee may establish a cash reserve for payment of any liability that is contingent or not currently payable;  4.
the Trustee may borrow funds required to pay Trust liabilities if fully repaid prior to further distributions to unitholders;  5.
the Trustee will make monthly cash distributions to unitholders (Note 3); and  6.
the Trust will terminate upon the first occurrence of:  a)
disposition of all net profits interests pursuant to terms of the Trust indenture;  b)
gross revenue of the Trust is less than $1 million per year for two successive years; or  c)
a vote of holders of 80% or more of the outstanding Trust units to terminate the Trust in accordance with provisions of the Trust indenture. 2. Basis of Accounting The financial
statements of the Trust are prepared on the following basis and are not intended to present financial position and results of operations in conformity with U.S. generally accepted accounting principles:  1.
net profits income is recorded in the month received by the Trustee (Note 3);  2.
interest income, interest to be received and distribution payable to unitholders include interest to be earned on net profits income from the monthly record date (last business day of the month) through the date of the
next distribution;  3.
trust expenses are recorded based on liabilities paid and cash reserves established by the Trustee for liabilities and contingencies; and  4.
distributions to unitholders are recorded when declared by the Trustee (Note 3).  30




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  The most significant differences between the Trusts financial statements and those
prepared in accordance with U.S. generally accepted accounting principles are:  1.
net profits income is recognized in the month received rather than accrued in the month of production;  2.
expenses are recognized when paid rather than when incurred; and  3.
cash reserves may be established by the Trustee for certain contingencies that would not be recorded under U.S. generally accepted accounting principles. This comprehensive basis of accounting corresponds to the accounting permitted for royalty trusts by the U.S. Securities and Exchange
Commission, as specified by Staff Accounting Bulletin Topic 12:E, Financial Statements of Royalty Trusts. Most accounting pronouncements
apply to entities whose financial statements are prepared in accordance with U.S. generally accepted accounting principles, directing such entities to accrue or defer revenues and expenses in a period other than when such revenues were received or
expenses were paid. Because the Trusts financial statements are prepared on the modified cash basis, as described above, most accounting pronouncements are not applicable to the Trusts financial statements. The Trustee reviews the Trusts net profits interests (NPI) in oil and gas properties for impairment whenever events or
circumstances indicate that the carrying value of the NPI may not be recoverable. In general, the Trustee does not view temporarily low
prices as an indication of impairment. The markets for crude oil and natural gas have a history of significant price volatility and though prices will occasionally drop significantly, industry prices over the long term will continue to be driven by
market supply and demand. If events and circumstances indicated the carrying value may not be recoverable, the Trustee would use the estimated undiscounted future net cash flows from the NPI to evaluate the recoverability of the Trust assets. If the
undiscounted future net cash flows from the NPI are less than the NPI carrying value, the Trust would recognize an impairment loss for the difference between the NPI carrying value and the estimated fair value of the NPI. The determination as to whether the NPI is impaired requires a significant amount of judgment by the Trustee and is based on the best
information available to the Trustee at the time of the evaluation. There was no impairment of the assets as of December 31, 2017. The initial carrying value of the net profits interests of $61,100,449 was XTO Energys historical net book value of the interests on
February 12, 1991, the date of the transfer to the Trust. Amortization of the net profits interests is calculated on a unit-of-production basis and charged
directly to trust corpus. Accumulated amortization was $51,789,115 as of December 31, 2017 and $51,196,649 as of December 31, 2016. Revenue Recognition In May 2014,
the FASB issued updated guidance for recognizing revenue from contracts with customers. This update amends the existing accounting standards for revenue recognition and is based on the principle that revenue should be recognized to depict the
transfer of goods and services to a customer at an amount that reflects the consideration a company expects to receive in exchange for those goods or services. The Trustee and XTO Energy do not believe the adoption of this standard will have a
significant impact on the Trusts financial statements due to the modified cash basis of reporting used by the Trust.  31




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  3. Distributions to Unitholders The Trustee determines the amount to be distributed to unitholders each month by totaling net profits income and other cash receipts, and
subtracting liabilities paid and adjustments in cash reserves established by the Trustee. The resulting amount (with estimated interest to be received on such amount through the distribution date) is distributed to unitholders of record within ten
business days after the monthly record date, the last business day of the month. Net profits income received by the Trustee consists of
net proceeds received in the prior month by XTO Energy from the underlying properties multiplied by the net profits percentage of 90% or 75%. Net proceeds are the gross proceeds received from the sale of production, less applicable costs. For the
90% net profits interests, such costs generally include production and property taxes, legal costs, and marketing and transportation charges. In addition to these costs, the 75% net profits interests include deductions for production expense and
development costs. XTO Energy, as owner of the underlying properties, computes net profits income separately for each of the five
conveyances. If costs exceed gross proceeds for any conveyance, such excess costs must be recovered, with accrued interest, from future net proceeds of that conveyance and cannot reduce net profits income from the other conveyances (Note 7). 4. Income Taxes For federal income tax
purposes, the Trust constitutes a fixed investment trust that is taxed as a grantor trust. A grantor trust is not subject to tax at the trust level. Accordingly, no provision for income taxes has been made in the financial statements. The
unitholders are considered to own the Trusts income and principal as though no trust were in existence. The income of the Trust is deemed to have been received or accrued by each unitholder at the time such income is received or accrued by the
Trust and not when distributed by the Trust. All revenues from the Trust are from sources within Texas, Oklahoma or New Mexico. Because
it distributes all of its net income to unitholders, the Trust has not been taxed at the trust level in New Mexico or Oklahoma. While the Trust has not owed tax, the Trustee is required to file an Oklahoma income tax return reflecting the income and
deductions of the Trust attributable to properties located in that state, along with a schedule that includes information regarding distributions to unitholders. Texas imposes a franchise tax on certain types of entities providing limited liability
protection, including trusts. However, the Trustee is, and expects to continue to be exempt from Texas franchise tax under the exemption for passive entities. Each unitholder should consult his or her own tax advisor regarding income tax requirements, if any, applicable to such persons
ownership of Trust units. 5. XTO Energy Inc. The underlying properties include approximately 15 overriding royalty interests in New Mexico that burden working interests owned and operated
by XTO Energy. These working interests were purchased by XTO Energy after the net profits interests were conveyed to the Trust. XTO Energy operates the Hewitt Unit, which is one of the properties underlying the Oklahoma 75% net profits interests.
Other than this property, XTO Energy and ExxonMobil do not operate or control any of the underlying properties or related working interests. In computing net profits income for the 75% net profits interests (Note 3), XTO Energy deducts an overhead charge as reimbursement for costs
associated with monitoring these interests. This charge at December 31, 2017  32




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  was $39,245 per month, or $470,940 annually (net to the Trust of $353,205 annually). Included in this monthly overhead charge is a charge XTO Energy deducts as operator of the Hewitt Unit. As of
December 31, 2017, overhead attributable to the Hewitt Unit was $5,607 per month, or $67,284 annually (net to the Trust of $50,463 annually). These overhead charges are subject to an annual adjustment based on an oil and gas industry index. On June 25, 2010, XTO Energy became a wholly owned subsidiary of Exxon Mobil Corporation. 6. Contingencies Several states have
enacted legislation requiring state income tax withholding from nonresident recipients of oil and gas proceeds. After consultation with its tax counsel, the Trustee believes that it is not required to withhold on payments made to the unitholders.
However, regulations are subject to change by the various states, which could change this conclusion. Should amounts be withheld on payments made to the Trust or the unitholders, distributions to the unitholders would be reduced by the required
amount, subject to the filing of a claim for refund by the Trust or unitholders for such amount. 7. Excess Costs If monthly costs exceed revenues for any conveyance, such excess costs must be recovered, with accrued interest, from future net proceeds of
that conveyance and cannot reduce net proceeds from other conveyances.  UnderlyingTX WI


OK WI


TotalCumulative excess costs remaining at 12/31/16

$
1,747,819


$
655,835


$
2,403,654Net excess costs (recovery) for the quarter ended 3/31/17


45,131



(317,927
)


(272,796
)Net excess costs (recovery) for the quarter ended 6/30/17


55,628



(249,993
)


(194,365
)Net excess costs (recovery) for the quarter ended 9/30/17


127,552



28,733



156,285Net excess costs (recovery) for the quarter ended 12/31/17


33,219



(116,648
)


(83,429
)Cumulative excess costs remaining at 12/31/17


2,009,349







2,009,349Accrued interest at 12/31/17


150,378







150,378Total remaining to be recovered at 12/31/17

$
2,159,727


$



$
2,159,727NPITX WI


OK WI


TotalCumulative excess costs remaining at 12/31/16

$
1,310,865


$
491,876


$
1,802,741Net excess costs (recovery) for the quarter ended 3/31/17


33,848



(238,445
)


(204,597
)Net excess costs (recovery) for the quarter ended 6/30/17


41,721



(187,495
)


(145,774
)Net excess costs (recovery) for the quarter ended 9/30/17


95,664



21,550



117,214Net excess costs (recovery) for the quarter ended 12/31/17


24,914



(87,486
)


(62,572
)Cumulative excess costs remaining at 12/31/17


1,507,012







1,507,012Accrued interest at 12/31/17


112,783







112,783Total remaining to be recovered at 12/31/17

$
1,619,795


$



$
1,619,795 XTO Energy advised the Trustee that continued lower oil prices in relation to operating expenses and increased
development costs resulted in net excess costs of $261,530 (NPI $196,147) on properties underlying the Texas working interests for the year ended December 31, 2017. This includes net excess costs of $33,219 ($24,914 net to the Trust) for the
quarter ended December 31, 2017.  33




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  XTO Energy advised the Trustee that increased oil revenue resulted in the complete recovery
of excess costs on properties underlying the Oklahoma working interests for the year ended December 31, 2017. Underlying excess costs of $180,050, including accrued interest of $63,402 (NPI $47,551) was recovered during the quarter ended
December 31, 2017. XTO Energy advised the trustee that continued lower oil prices resulted in net excess costs of $788,668 ($591,501
net to the Trust) on properties underlying the Texas working interest for the year ended December 31, 2016. This includes net excess costs of $208,740 ($156,555 net to the Trust) for the quarter ended December 31, 2016. XTO Energy advised the trustee that improved oil prices and decreased costs resulted in the partial recovery of excess costs of $411,085
($308,314 net to the Trust) on properties underlying the Oklahoma working interest for the year ended December 31, 2016. This includes the partial recovery of $146,946 ($110,209 net to the Trust) for the quarter ended December 31, 2016. XTO Energy advised the trustee that lower oil prices resulted in net excess costs of $905,180 ($678,885 net to the Trust) on properties
underlying the Texas working interest for the year ended December 31, 2015. This includes net excess costs of $95,651 ($71,738 net to the Trust) for the quarter ended December 31, 2015. XTO Energy advised the trustee that timing of cash receipts, lower oil prices and decreased oil production resulted in net excess costs of
$1,066,920 ($800,190 net to the Trust) on properties underlying the Oklahoma working interest for the year ended December 31, 2015. This includes net excess costs of $206,713 ($155,035 net to the Trust) for the quarter ended December 31,
2015. Underlying cumulative excess costs for the Texas working interest conveyance remaining as of December 31, 2017 totaled
$2.2 million, including accrued interest of $0.2 million. 8. Supplemental Oil and Gas Reserve Information (Unaudited) Oil and Natural Gas Reserves Proved oil and gas reserves have been estimated by independent petroleum engineers. Proved reserves are those quantities of oil and natural
gas, which, by analysis of geoscience and engineering data can be estimated with reasonable certainty to be economically producible from a given date forward, from known reservoirs and under existing economic conditions, operating methods, and
government regulation before the time at which contracts providing the right to operate expire, unless evidence indicates that renewal is reasonably certain. Proved developed reserves are the quantities expected to be recovered through existing
wells with existing equipment and operating methods in which the cost of the required equipment is relatively minor compared with the cost of a new well. Due to the inherent uncertainties and the limited nature of reservoir data, such estimates are
subject to change as additional information becomes available. The reserves actually recovered and the timing of production of these reserves may be substantially different from the original estimate. Revisions result primarily from new information
obtained from development drilling and production history and from changes in economic factors. Standardized Measure The standardized measure of discounted future net cash flows and changes in such cash flows are prepared using assumptions required by the
Financial Accounting Standards Board. Such assumptions include the use of 12-month average prices for oil and gas, based on the first-day-of-the-month price for each month in the period,  34




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  and year end costs for estimated future development and production expenditures to produce the proved reserves, including recovery of cumulative excess costs remaining at year end. Future net
cash flows are discounted at an annual rate of 10%. No provision is included for federal income taxes since future net cash flows are not subject to taxation at the trust level. The standardized measure does not represent managements estimate of future cash flows or the value of proved oil and gas reserves.
Probable and possible reserves, which may become proved in the future, are excluded from the calculations. Furthermore, prices used to determine the standardized measure are influenced by supply and demand as affected by recent economic conditions
as well as other factors and may not be the most representative in estimating future revenues or reserve data. Estimated costs to plug
and abandon wells on the underlying working interest properties at the end of their productive lives have not been deducted from cash flows since this is not a legal obligation of the Trust. These costs are the legal obligation of XTO Energy as the
owner of the underlying working interests and will only be deducted from net proceeds payable to the Trust if net proceeds from the related conveyance exceed such costs when paid, subject to excess cost carryforward provisions (Note 3). Oil prices used to determine the standardized measure were based on average realized oil prices of $47.08 per Bbl in 2017, $38.19 per Bbl in
2016, $46.58 per Bbl in 2015 and $88.53 per Bbl in 2014. The weighted average realized gas prices used to determine the standardized measure were $3.14 per Mcf in 2017, $2.45 per Mcf in 2016, $2.83 per Mcf in 2015 and $5.82 per Mcf in 2014. Reserve quantities and revenues for the net profits interests were estimated from projections of reserves and revenues attributable to the
underlying properties. Since the Trust has defined net profits interests, the Trust does not own a specific percentage of the oil and gas reserves. Oil and gas reserves are allocated to the net profits interests by dividing Trust net cash inflows by
12-month average oil and gas prices. Any fluctuations in 12-month average prices or estimated costs will result in revisions to the estimated reserve quantities
allocated to the net profits interests, which may not correlate with revisions of underlying proved reserves.  35




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  Proved Reserves  Net Profits Interests


UnderlyingProperties90% NetProfits Interests


75% NetProfits Interests


Total(in thousands)

Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)Balance, December 31, 2014


454



19,911



535



175



989



20,086



2,318



22,828Extensions, additions and discoveries


14



142











14



142



16



158Revisions of prior estimates


25



(2,198
)


(477
)


(142
)


(452
)


(2,340
)


(1,264
)


(2,828
)Production


(65
)


(1,409
)


(3
)






(68
)


(1,409
)


(232
)


(1,616
)Balance, December 31, 2015


428



16,446



55



33



483



16,479



838



18,542Extensions, additions and discoveries


6



110











6



110



7



122Revisions of prior estimates


38



800



62



(4
)


100



796



622



902Production


(66
)


(1,896
)










(66
)


(1,896
)


(224
)


(2,049
)Balance, December 31, 2016


406



15,460



117



29



523



15,489



1,243



17,517Extensions, additions and discoveries


10



54











10



54



11



61Revisions of prior estimates


639



2,857



187



38



826



2,895



1,294



3,282Production


(55
)


(1,350
)


(4
)






(59
)


(1,350
)


(213
)


(1,535
)Balance, December 31, 2017


1,000



17,021



300



67



1,300



17,088



2,335



19,325 Extensions, additions and discoveries of proved gas reserves are primarily because of development in the Mid-Continent area. Revisions of prior estimates are primarily related to changes in prices and costs. Negative revisions for the underlying properties in 2015 are primarily due to lower oil and gas prices. Positive
revisions for the underlying properties in 2016 are primarily due to lower operating costs. Positive revisions for 2017 are primarily due to higher prices. Proved Developed Reserves  Net Profits Interests


UnderlyingProperties90% NetProfits Interests


75% NetProfits Interests


Total(in thousands)

Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)


Oil(Bbls)


Gas(Mcf)December 31, 2014


454



19,911



535



175



989



20,086



2,318



22,828December 31, 2015


428



16,446



55



33



483



16,479



838



18,542December 31, 2016


406



15,460



117



29



523



15,489



1,243



17,517December 31, 2017


1,000



17,021



300



67



1,300



17,088



2,335



19,325  36




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  Standardized Measure of Discounted Future Net Cash Flows from Proved Reserves  90% Net Profits Interests


75% Net Profits Interests


TotalDecember 31


December 31


December 31(in thousands)

2017


2016


2015


2017


2016


2015


2017


2016


2015Net Profits InterestsFuture cash inflows

$
101,022


$
53,629


$
65,055


$
14,163


$
4,477


$
2,915


$
115,185


$
58,106


$
67,970Future production taxes


(8,366
)


(4,529
)


(5,482
)


(1,019
)


(322
)


(230
)


(9,385
)


(4,851
)


(5,712
)Future net cash flows


92,656



49,100



59,573



13,144



4,155



2,685



105,800



53,255



62,25810% discount factor


(46,061
)


(22,605
)


(27,789
)


(5,694
)


(1,266
)


(727
)


(51,755
)


(23,871
)


(28,516
)Standardized measure

$
46,595


$
26,495


$
31,784


$
7,450


$
2,889


$
1,958


$
54,045


$
29,384


$
33,742Underlying PropertiesFuture cash inflows


$
170,557


$
90,456


$
91,575Future costs



(50,078
)


(30,362
)


(21,803
)Future net cash flows



120,479



60,094



69,77210% discount factor



(58,774
)


(26,805
)


(31,846
)Standardized measure


$
61,705


$
33,289


$
37,926 Changes in Standardized Measure of Discounted Future Net Cash Flows from Proved Reserves  (in thousands)

90% Net Profits Interests


75% Net Profits Interests


Total2017


2016


2015


2017


2016


2015


2017


2016


2015Net Profits InterestsStandardized measure, January 1

$
26,495


$
31,784


$
69,264


$
2,889


$
1,958


$
26,671


$
29,384


$
33,742


$
95,935Extensions, additions and discoveries


353



290



634















353



290



634Accretion of discount


2,273



2,719



5,864



310



174



2,367



2,583



2,893



8,231Revisions of prior estimates, changes in price and
    other


23,941



(756
)


(35,307
)


4,405



757



(26,866
)


28,346



1



(62,173
)Net profits income


(6,467
)


(7,542
)


(8,671
)


(154
)






(214
)


(6,621
)


(7,542
)


(8,885
)Standardized measure, December 31

$
46,595


$
26,495


$
31,784


$
7,450


$
2,889


$
1,958


$
54,045


$
29,384


$
33,742Underlying PropertiesStandardized measure, January 1


$
33,289


$
37,926


$
112,521Revisions:Prices and costs



12,824



(11,714
)


(50,293
)Quantity estimates



20,848



12,511



(24,841
)Accretion of discount



2,941



3,252



9,673Future development costs



(1,197
)


(998
)


(1,896
)Other



(2
)


(8
)


5Net revisions



35,414



3,043



(67,352
)Extensions, additions and discoveries



393



322



704Production



(8,588
)


(9,000
)


(10,645
)Development costs



1,197



998



2,698Net change



28,416



(4,637
)


(74,595
)Standardized measure, December 31


$
61,705


$
33,289


$
37,926  37




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##### Table of Contents

CROSS TIMBERS ROYALTY TRUST NOTES TO FINANCIAL STATEMENTS(Continued)  9. Quarterly Financial Data (Unaudited) The following is a summary of net profits income, distributable income and distributable income per unit by quarter for 2017 and 2016:  Net ProfitsIncome


DistributableIncome


DistributableIncomeper Unit2017First Quarter

$
1,624,671


$
1,383,420


$
0.230570Second Quarter


1,633,117



1,521,552



0.253592Third Quarter


1,674,186



1,526,430



0.254405Fourth Quarter


1,689,363



1,622,388



0.270398$
6,621,337


$
6,053,790


$
1.0089652016First Quarter

$
2,706,106


$
2,180,982


$
0.363497Second Quarter


1,391,073



975,180



0.162530Third Quarter


1,513,537



1,299,912



0.216652Fourth Quarter


1,930,990



1,908,726



0.318121$
7,541,706


$
6,364,800


$
1.060800  38




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##### Table of Contents

Item 9.
Changes in and Disagreements with Accountants on Accounting and Financial Disclosure None.  Item 9A.
Controls and Procedures Conclusion Regarding the Effectiveness of Disclosure
Controls and Procedures The Trustee conducted an evaluation of the Trusts disclosure controls and procedures, as such term is
defined under Rule 13a-15(e) promulgated under the Securities Exchange Act of 1934, as amended. Based on this evaluation, the Trustee has concluded that the Trusts disclosure controls and procedures were
effective as of the end of the period covered by this annual report. In its evaluation of disclosure controls and procedures, the Trustee has relied, to the extent considered reasonable, on information provided by XTO Energy. Trustees Report on Internal Control Over Financial Reporting The Trustee is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Rule
13a-15(f) promulgated under the Securities Exchange Act of 1934, as amended. The Trustee conducted an evaluation of the effectiveness of the Trusts internal control over financial reporting based on the
criteria established in Internal ControlIntegrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on the Trustees evaluation under the framework in Internal
ControlIntegrated Framework (2013), the Trustee concluded that the Trusts internal control over financial reporting was effective as of December 31, 2017. The effectiveness of the Trusts internal control over
financial reporting as of December 31, 2017 has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report under Item 8, Financial Statements and Supplementary Data. Changes in Internal Control Over Financial Reporting There were no changes in the Trusts internal control over financial reporting during the quarter ended December 31, 2017 that have
materially affected, or are reasonably likely to materially affect, the Trusts internal control over financial reporting.  Item 9B.
Other Information None.  39




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##### Table of Contents

PART III  Item 10.
Directors, Executive Officers and Corporate Governance (a)
Directors, Officers and Committees.    The Trust has no directors, executive officers, audit committee, audit committee financial expert, compensation committee or nominating committee. The Trustee is a corporate trustee
which may be removed, with or without cause, by the affirmative vote of the holders of a majority of all the units then outstanding. (b)
Section16 (a) Beneficial Ownership Reporting Compliance.    Section 16(a) of the Securities Exchange Act of 1934 requires that directors, officers, and beneficial owners of more than 10% of the
registrants equity securities file initial reports of beneficial ownership and reports of changes in beneficial ownership with the Securities and Exchange Commission and the New York Stock Exchange. To the Trustees knowledge, based
solely on the information furnished to the Trustee, the Trustee is unaware of any person that failed to file on a timely basis reports required by Section 16(a) filing requirements with respect to the Trust units of beneficial interest during
and for the year ended December 31, 2017. (c) Code of Ethics.    Because the Trust has no employees, it
does not have a code of ethics. Employees of the Trustee, Simmons Bank, must comply with the banks code of ethics which may be found at ir.simmonsbank.com/govdocs.  Item 11.
Executive Compensation (a) Compensation Committee Interlocks
and Insider Participation/Compensation Committee Report.    The Trust has no officers or directors and is administered by a trustee. The Trust does not have a compensation committee or maintain any equity compensation plans
and there are no units reserved for issuance under such plans. (b) Compensation of the Trustee.    Southwest
Bank, the prior trustee, received the following annual compensation for the fiscal years ended December 31, 2015 through December 31, 2017 as specified in the Trust indenture:  2017


2016


2015Southwest Bank, Trustee(1)

$
77,631


$
32,437


$
35,792  (1)
Under the Trust indenture, the trustee is entitled to an administrative fee of: (i) 1/20 of 1% of the first $100 million of the annual gross revenue of the Trust, and 1/30 of 1% of the annual gross revenue of the
Trust in excess of $100 million, and (ii) trustees standard hourly rates for time in excess of 300 hours annually. (c) Pay Ratio Disclosure.    The Trust does not have a principal executive officer or employees and therefore, the
pay ratio disclosure is not applicable.  Item 12.
Security Ownership of Certain Beneficial Owners and Management and Related Unitholder Matters (a) Equity Compensation Plans and Trust Repurchases.    The Trust has no equity compensation plans. The Trust has
not repurchased any units during the fourth quarter of fiscal 2017. (b) Security Ownership of Certain Beneficial
Owners.    The Trustee is not aware of any person who beneficially owns more than 5% of the outstanding units. (c)Security Ownership of Management.    The Trust has no directors or executive officers. As of February 22,
2018, Simmons Bank beneficially held 300 units, less than one percent of the outstanding units. Simmons Bank has sole power to dispose of these units and sole voting power.  40




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(d) Changes in Control.    The Trustee knows of no arrangements
which may subsequently result in a change in control of the Trust.  Item 13.
Certain Relationships and Related Transactions, and Director Independence In computing net profits income paid to the Trust for the 75% net profits interests, XTO Energy deducts an overhead charge as reimbursement for
costs associated with monitoring these interests. This charge at December 31, 2017 was $39,245 per month, or $470,940 annually (net to the Trust of $353,205 annually). Included in this monthly overhead charge is a charge XTO Energy deducts as
operator of the Hewitt Unit. As of December 31, 2017 overhead attributable to the Hewitt Unit was $5,607 per month, or $67,284 annually (net to the Trust of $50,463 annually). These overhead charges are subject to annual adjustment based on an
oil and gas industry index. See Item 11, Executive Compensation, for the remuneration received by the Trustee for the fiscal years ended
December 31, 2015 through December 31, 2017. As noted in Item 10, Directors, Executive Officers and Corporate Governance, the
Trust has no directors, executive officers, audit committee, audit committee financial expert, compensation committee or nominating committee. The Trustee is a corporate trustee which may be removed, with or without cause, by the affirmative vote of
the holders of a majority of all the units then outstanding.  Item 14.
Principal Accountant Fees and Services Fees for services performed
by PricewaterhouseCoopers LLP for the years ended December 31, 2017 and 2016 are:  2017


2016Audit fees-PwC

$
142,000


$
132,129Audit-related fees






Tax fees






All other fees






$
142,000


$
132,129 As referenced in Item 10, Directors, Executive Officers and Corporate Governance, above, the Trust has no
audit committee, and as a result, has no audit committee pre-approval policy with respect to fees paid to PricewaterhouseCoopers LLP.  41




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PART IV  Item 15.
Exhibits and Financial Statement Schedules  (a)
The following documents are filed as a part of this report:  1.
Financial Statements (included in Item 8 of this report) Report of Independent
Registered Public Accounting Firm Statements of Assets, Liabilities and Trust Corpus at December 31, 2017 and 2016 Statements of Distributable Income for the years ended December 31, 2017, 2016 and 2015 Statements of Changes in Trust Corpus for the years ended December 31, 2017, 2016 and 2015 Notes to Financial Statements  2.
Financial Statement Schedules Financial statement schedules are omitted because of the
absence of conditions under which they are required or because the required information is given in the financial statements or notes thereto.  3.
Exhibits  (4)(a)
Cross Timbers Royalty Trust Indenture amended and restated on January 13, 1992 by NationsBank, N.A., as Trustee, heretofore filed as Exhibit 3.1 to the Trusts Registration Statement No. 33-44385 filed with the Securities and Exchange Commission on February 19, 1992, is incorporated herein by reference.  (b)
Net Overriding Royalty Conveyance (Cross Timbers Royalty Trust, 90%Texas) from South Timbers Limited Partnership, West Timbers Limited Partnership, North Timbers Limited Partnership, East Timbers Limited
Partnership, Hickory Timbers Limited Partnership, and Cross Timbers Partners, L.P. (predecessors of XTO Energy) to NCNB Texas National Bank, as Trustee, dated February 12, 1991 (without Schedules A and B), heretofore filed as Exhibit 10.1 to
the Trusts Registration Statement No. 33-44385 filed with the Securities and Exchange Commission on February 19, 1992, is incorporated herein by reference.  (c)
Correction to Net Overriding Royalty Conveyance (Cross Timbers Royalty Trust, 90%Texas) from South Timbers Limited Partnership, West Timbers Limited Partnership, North Timbers Limited Partnership, East Timbers
Limited Partnership, Hickory Timbers Limited Partnership, and Cross Timbers Partners, L.P. (predecessors of XTO Energy) to NCNB Texas National Bank, as Trustee, dated September 23, 1991 (without Schedules A and B), heretofore filed as Exhibit
10.2 to the Trusts Registration Statement No. 33-44385 filed with the Securities and Exchange Commission on February 19, 1992, is incorporated herein by reference.  (d)
Net Overriding Royalty Conveyance (Cross Timbers Royalty Trust, 75%Texas) from South Timbers Limited Partnership, West Timbers Limited Partnership, North Timbers Limited Partnership, East Timbers Limited
Partnership, Hickory Timbers Limited Partnership, and Cross Timbers Partners, L.P. (predecessors of XTO Energy) to NCNB Texas National Bank, as Trustee, dated February 12, 1991 (without Schedules A and B), heretofore filed as Exhibit 10.5 to
the Trusts Registration Statement No. 33-44385 filed with the Securities and Exchange Commission on February 19, 1992, is incorporated herein by reference.  (23)
Consent of Miller and Lents, Ltd.  42




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(31)
Rule 13a-14(a)/15d-14(a) Certification  (32)
Section 1350 Certification  (99.1)
Miller and Lents, Ltd. Report Copies of the above Exhibits
are available to any unitholder, at the actual cost of reproduction, upon written request to the Trustee, Simmons Bank, P.O. Box 962020, Fort Worth, Texas 76162-2020.  43




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SIGNATURES Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this Report to
be signed on its behalf by the undersigned thereunto duly authorized.  CROSS TIMBERS ROYALTY TRUSTBy SIMMONS BANK, TRUSTEEBy

/S/ LEE ANN ANDERSONLee Ann AndersonSenior Vice PresidentEXXON MOBIL CORPORATIONDate: March 12, 2018



By

/S/ DAVID LEVYDavid LevyVice PresidentUpstream Business Service (The Trust has no directors or executive officers.)  44