Table of Contents Index to Financial Statements (6) Pre-tax PV-10 (a non-GAAP measure) is one measure of the value of a company’s proved reserves that we believe is used by securities analysts to compare relative values among peer companies without regard to income taxes. The reconciling difference in pre-tax PV-10 and the after-tax PV-10, or standardized measure, is the discounted value of future income taxes on the estimated cash flows from our proved natural gas, oil and NGL reserves. Our existing tax attributes, including net operating losses and remaining depreciable tax basis related to our natural gas and oil properties, more than offset our future net operating income, resulting in no tax effect to our PV-10 calculation for the year ended December 31, 2020. (7) Includes future asset retirement obligations outside of Appalachia. (8) Based upon pre-tax PV-10 of proved developed producing activities. Lease Expirations We refer you to  “Supplemental Oil and Gas Disclosures”  in Item 8 of Part II of this Annual Report for a more detailed discussion of our proved natural gas, oil and NGL reserves as well as our standardized measure of discounted future net cash flows related to our proved natural gas, oil and NGL reserves. We also refer you to the risk factor “Our proved natural gas, oil and NGL reserves are estimates that include uncertainties. Any material changes to these uncertainties or underlying assumptions could cause the quantities and net present value of our reserves to be overstated or understated” in  Item 1A of Part I of this Annual Report and to  “Management’s Discussion and Analysis of Financial Condition and Results of Operations – Cautionary Statement about Forward-Looking Statements”  in Item 7 of Part II of this Annual Report for a discussion of the risks inherent in utilization of standardized measures and estimated reserve data. For the years ended December 31, Net acreage expiring: 2021 2022 2023 Northeast Appalachia 5,861  6,460  6,921  Southwest Appalachia  36,690  20,149  11,986  Other US – Other Exploration 5,683  646  —  US – Sand Wash Basin 3,435  —  —  Canada – New Brunswick  2,518,519  —  —  (1) (2) (1) (3) The following table summarizes the leasehold acreage expiring over the next three years, assuming successful wells are not drilled to develop the acreage and leases are not extended: (1) We have no reported proved undeveloped locations expiring in 2021. (2) The leasehold acreage expiring includes 8,907 acres acquired through the Montage Merger that are subject to annual extension options at our sole discretion. Excluding this acreage, of the remaining leasehold acreage expiring, 17,460 net acres in 2021, 6,173 net acres in 2022 and 5,573 net acres in 2023 can be extended for an average 4.9 years. (3) Exploration licenses were extended through March 2021 but have been subject to a moratorium since 2015. We are currently working with Canadian officials to extend our licenses, although we cannot assure that the licenses will be extended past March 2021. We fully impaired our investment in New Brunswick in 2016. 9