Exhibit 99.1

RIVIERA RESOURCES REPORTS FIRST QUARTER 2020 RESULTS

HOUSTON, May 7, 2020 – Riviera Resources, Inc. (OTCQX: RVRA) (“Riviera” or the “Company”) and its wholly owned subsidiary, Blue Mountain Midstream LLC (“Blue Mountain”) announces financial and operating results for the first quarter 2020 and provides a strategic update.

The Company highlights the following accomplishments:

Blue Mountain highlights:

Riviera Upstream highlights:

David Rottino, Riviera’s President and Chief Executive Officer, commented, “In the first quarter, the Company outperformed upstream Adjusted EBITDAX guidance, closed four transactions for proceeds of approximately $69 million, and announced a $1.00 cash distribution, returning approximately $60 million to shareholders in April 2020. In addition, we paid a $4.25 cash distribution to shareholders in December 2019, returning approximately $250 million, and recently announced another cash distribution $0.75 per share payable on May 12,2020, that will return over $45 million to shareholders. We also remain committed to reducing operating and general and administrative costs to optimally manage the business during this market downturn, and recently announced the consolidation of management of Blue Mountain within the Company’s existing executive management team. With our continued focus on reducing costs, strong asset base, and a midstream business that is optimally positioned in the Anadarko basin, the Company is well positioned to sustain its business during this downturn.”

Key Financial Results ⁽¹⁾

Cost Reduction Initiatives

General and Administrative Costs

The Company remains focused on finding ways to continue to reduce general and administrative costs, and recently announced the consolidation of management of Blue Mountain with the Company’s existing executive management team, while continuing to maintain separate capital structures for each entity. In the first quarter of 2020, Riviera Upstream’s general and administrative expenses, excluding share-based compensation expenses and severance expenses, were approximately $8.5 million. The Company expects by fourth quarter 2020, Upstream’s general and administrative expenses, excluding share-based compensation expenses and severance expenses, will be approximately $4.4 million. This represents a 48% decrease from the first quarter 2020.

Operating Expenses

The Company has taken several proactive steps to significantly reduce lease operating expenses, including a reduction in workforce, optimizing compression and well workover programs, and negotiating lower overall service costs. With respect to operating costs, the Company has lowered costs by reducing workover activity, reducing workforce, releasing equipment, and negotiating lower rates for saltwater disposal and chemicals. As result, the Company estimates the Upstream’s lease operating costs to be $14 million to $16 million in 2020, a 25% decrease from the mid-point of previously estimated lease operating expenses of $19 million to $21 million.

Capital Expenses

As previously announced, the Company has decided to defer initiating its operated drilling program in the Ruston Field of North Louisiana, reducing its 2020 budgeted capital by approximately $21 million. As the planned program was not scheduled to begin until late in the year, the impact to previously estimated 2020 production and EBITDA is minimal. Because the acreage is held by production, the Company has the flexibility to drill at a later date without the risk of losing its current leases. The reliability and results of development locations in the Ruston field are still encouraging, with expected IRR over 100% at $2.75/MMbtu gas prices. If prices do improve throughout the year, Riviera will maintain the option to re-initiate the program.

Opportunistic Asset Monetizations

In the first quarter of 2020 the Company closed four transactions generating aggregate proceeds of approximately $69 million. The four transactions include the sale of properties located in the Uinta Basin (closed January 2020), the sale of properties located in East Texas (Overton field closed January 2020 and Personville field closed February 2020), and the Oklahoma City Office building (closed February 2020).

Return of Capital to Shareholders

Thus far in 2020, the Company has returned or announced approximately $107 million of capital to shareholders through a $1.00 per share cash distribution paid to shareholders on April 24, 2020, a $0.75 per share cash distribution payable on May 12, 2020, and share repurchases.

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On July 18, 2019, the Company’s Board of Directors increased the share repurchase authorization to $150 million of the Company’s outstanding shares of common stock. As of April 30, 2020, approximately $22 million was available for share repurchase under the program.

First Quarter 2020 Activity – Upstream Assets

The Company performed in line with expectations in the first quarter with respect to its upstream assets. Production for the first quarter averaged approximately 72 MMcfe/d, in line with our guidance range. Upstream capital expenditures were approximately $0.7 million, operating expenses were approximately $7.7 million and adjusted general and administrative expenses were approximately $8.5 million, all in line with our guidance for the quarter.

Blue Mountain Business Update    

First Quarter 2020 Activity

In the first quarter of 2020, natural gas throughput on Blue Mountain’s system averaged 118 MMcf/d, relatively flat compared to the fourth quarter of 2019.    Blue Mountain continued tying in new wells and turned 14 wells to sales throughout the quarter.

With respect to its water business, Blue Mountain continues to make considerable progress on the buildout of its water gathering system. During the first quarter, Blue Mountain managed 3.7 million barrels of water in total, or approximately 40,600 barrels per day. Of that total, the Company moved over 23,300 barrels per day on pipe (up 102% from fourth quarter 2019). With 57% of managed water on Blue Mountain pipe, Blue Mountain exceeded its guidance range. Furthermore, Blue Mountain completed construction of its third wholly owned and operated salt water disposal well (“SWD”)

Blue Mountain began construction of its crude oil gathering system in October 2019. The initial segments on its South system were placed in service on February 1, 2020 and the initial segments on its North system were placed in service on March 2, 2020.

Capital expenditures were $13 million for the first quarter of 2020, with the majority of capital being spent on water and crude oil gathering pipelines. First quarter capital expenditures exceeded guidance due to the acceleration of certain projects. Full year 2020 Blue Mountain capital is expected to be approximately $25 million, which is 11% lower than prior guidance estimate.

Cost Reduction Initiatives

In the first quarter of 2020, Blue Mountain Midstream’s general and administrative expenses, excluding share-based compensation expenses and severance expenses, were approximately $2.9 million. The Company recently consolidated the management of Blue Mountain within its existing executive management team, while continuing to maintain a separate capital structure for Blue Mountain. With consolidation of Blue Mountain’s management team with the existing Riviera management team, and other cost reduction initiatives, the Company expects by fourth quarter 2020, Blue Mountain’s general and administrative expenses, excluding share-based compensation and severance expenses, will be approximately $2.1 million. This represents a 28% decrease from the first quarter 2020.

Recent Throughput

Starting in April, due to consistently low commodity prices, certain producers have elected to shut-in portions of their production. As a result, Blue Mountain expects to see lower second quarter throughput at its processing plant versus prior quarter, with throughput of approximately 80 MMcf/d at the end of April, approximately 32% lower than average throughput in the first quarter of 2020. Given the dynamic environment, the Company has chosen not to provide second quarter guidance for Blue Mountain.

Balance Sheet and Liquidity

Riviera and Blue Mountain have established separate credit facilities. As of March 31, 2020, Riviera held approximately $155 million of cash, and there were no borrowings outstanding on Riviera’s revolving credit facility (the “Riviera Credit Facility”). Riviera had borrowing commitments of up to $90 million with available borrowing capacity of approximately $89 million, inclusive of outstanding letters of credit. Redetermination of the borrowing base under the Riviera Credit Facility occurs semi-annually, in April and October. The Riviera Credit Facility borrowing base is expected to be reduced as a result of the spring redetermination.

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As of March 31, 2020, Blue Mountain held approximately $10 million of cash, and had approximately $73 million drawn on its revolving credit facility. Blue Mountain had borrowing commitments of up to $200 million with available borrowing capacity of approximately $115 million, including outstanding letters of credit, subject to covenant restrictions in the Blue Mountain Credit Facility.    

As of April 30, 2020, there were no borrowings on the Riviera Credit Facility, and $75 million drawn on the Blue Mountain Credit Facility.

First Quarter Actuals

Below is a summary of the Company’s consolidated first quarter results.

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Upstream Segment - First Quarter Actuals versus Guidance

The comparison to guidance below is for the upstream assets only.

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Blue Mountain Midstream Segment - First Quarter Actuals versus Guidance

The comparison to guidance below is for the Blue Mountain business only for the first quarter of 2020.

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Upstream Segment - Second Quarter and Full Year 2020 Guidance

The guidance below is for the Upstream assets only. Guidance estimates have been adjusted for asset sales closed in the first quarter of 2020.

The Company expects to have negative Adjusted EBITDAX in the second quarter largely due to on-going general and administrative costs associated with managing recently divested assets during the transition period. Additionally, the Company expects to incur severance expenses in the first half of the year. In the second half of 2020, the Company expects to generate positive Adjusted EBITDAX as the cost structure aligns with the on-going asset base.

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Hedging Update

Riviera Upstream Hedges

Earnings Call / Form 10-Q

The Company will host a conference call Thursday, May 7, 2020 at 10:00 a.m. (Central) to discuss the Company’s first quarter 2020 results and expects to file its first quarter Form 10-Q for the three months ended March 31, 2020 with the U.S. Securities and Exchange Commission on or around that date. There will be prepared remarks by executive management followed by a question and answer session.

Investors and analysts are invited to participate in the call by dialing (866) 416-7462, or (409) 217-8223 for international calls using Conference ID: 5944979. Interested parties may also listen over the internet at www.rivieraresourcesinc.com. A replay of the call will be available on the Company’s website.

Supplemental information can be found at the following link on our website: http://ir.rivieraresourcesinc.com/events-and-presentations

ABOUT RIVIERA RESOURCES

Riviera Resources, Inc. is an independent oil and natural gas company with a strategic focus on efficiently operating and developing its assets, and returning capital to its shareholders. Riviera’s properties are primarily located in North Louisiana, and the Mid-Continent regions. Additionally, the Company owns Blue Mountain Midstream LLC, a midstream company centered in the core of the Merge play in the Anadarko Basin.

Non-GAAP Financial Measures and Selected Items Impacting Comparability

To supplement our financial information presented in accordance with GAAP, management uses additional measures known as “non-GAAP financial measures” in its evaluation of past performance and prospects for the future. The primary additional measures used by management are earnings before interest, taxes, depreciation and amortization, exploration costs, noncash gains and losses on commodity derivatives, accrued settlements on commodity derivative contracts related to current production period, share-based compensation expenses, gains and losses on asset sales and other, reorganization items, and asset impairments (“Adjusted EBITDAX”) and earnings before interest, taxes, depreciation and amortization, noncash gains and losses on commodity derivatives, accrued settlements on commodity derivative contracts related to current production period, share-based compensation expenses, gains and losses on asset sales and other, and asset impairments (“Adjusted EBITDA”). Management believes these non-GAAP financial measures provide useful information to investors because these non-GAAP measures, when viewed with the Company’s GAAP results and accompanying reconciliations, provide a more complete understanding of the Company’s performance than GAAP results alone.

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Forward-Looking Statements

Statements made in this press release that are not historical facts are “forward-looking statements.” These statements are based on certain assumptions and expectations made by the Company which reflect management’s experience, estimates and perception of historical trends, current conditions, and anticipated future developments. These statements include, among others, statements regarding our 2020 guidance, planned capital expenditures, increases in oil and gas production, the number of anticipated wells to be drilled or completed after the date hereof, future cash flows and borrowings, our strategic objectives with respect to Blue Mountain Midstream, our engagement of financial advisors with respect to strategic alternatives, our financial position, business strategy and other plans and objectives for future operations. Such statements are subject to a number of assumptions, risks and uncertainties, many of which are beyond the control of the Company, which may cause actual results to differ materially from those implied or anticipated in the forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, volatility of oil, natural gas and natural gas liquid prices or a prolonged period of low oil, natural gas or natural gas liquid prices and the effects of actions by, or disputes among or between, members of the Organization of Petroleum Exporting Countries and other oil producing nations, such as Saudi Arabia, and other oil and natural gas producing countries, such as Russia, with respect to production levels or other matters related to the price of oil, the effects of excess supply of oil and natural gas resulting from the reduced demand caused by the novel coronavirus disease global pandemic and the actions by certain oil and natural gas producing countries, market prices for oil, natural gas and NGLs, production volumes, estimates of proved reserves, capital expenditures, the capacity and utilization of midstream facilities, economic and competitive conditions, credit and capital market conditions, regulatory changes and other uncertainties. These and other important factors could cause actual results to differ materially from those anticipated or implied in the forward-looking statements. Please read “Risk Factors” in the Company’s Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and other public filings. The Company undertakes no obligation to publicly update any forward-looking statements, whether as a result of new information or future events.

CONTACT:

Investor Relations

(281) 840-4168

IR@RVRAresources.com

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CONDENSED CONSOLIDATED BALANCE SHEETS

(Unaudited)

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CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)

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CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

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Adjusted EBITDAX (Non-GAAP Measure)

The non-GAAP financial measure of Adjusted EBITDAX, as defined by the Company, may not be comparable to similarly titled measures used by other companies. Therefore, this non-GAAP measure should be considered in conjunction with net income (loss) and other performance measures prepared in accordance with GAAP. Adjusted EBITDAX should not be considered in isolation or as a substitute for GAAP.

Adjusted EBITDAX is a measure used by Company management to evaluate the Company’s operational performance and for comparisons to the Company’s industry peers. Management also believes this information may be useful to investors and analysts to gain a better understanding of the Company’s financial results.

The following presents a reconciliation of net income (loss) to Adjusted EBITDAX:

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Adjusted EBITDAX and Adjusted EBITDA (Non-GAAP Measures)

The non-GAAP financial measures of Adjusted EBITDAX and Adjusted EBITDA, as defined by the Company, may not be comparable to similarly titled measures used by other companies. Therefore, these non-GAAP measures should be considered in conjunction with net income (loss) and other performance measures prepared in accordance with GAAP. Adjusted EBITDAX and Adjusted EBITDA should not be considered in isolation or as a substitute for GAAP.

Adjusted EBITDAX and Adjusted EBITDA are measures used by Company management to evaluate the Company’s operational performance and for comparisons to the Company’s industry peers. Management also believes this information may be useful to investors and analysts to gain a better understanding of the Company’s financial results.

The following presents a reconciliation of net income (loss) to Adjusted EBITDAX and Adjusted EBITDA:

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Exhibit 99.2

RIVIERA RESOURCES

FIRST QUARTER AND 2020 EARNINGS CALL SCRIPT

May 7^th, 2020 - 10 a.m. Central Time

Management Participants:

MANAGEMENT DISCUSSION

Paula Melancon:

Good morning and welcome to Riviera Resources’ first quarter 2020 earnings conference call. Today’s call is being recorded. This is Paula Melancon, Director of Investor Relations, and in a moment I will introduce David Rottino, our President and Chief Executive Officer, but first I need to provide you with disclosure regarding forward-looking statements that will be made during this call. The statements describing our beliefs, goals, plans, strategies, expectations, projections, forecasts, and assumptions are forwardlooking statements. Please note that the Company’s actual results may differ from those anticipated by such forward-looking statements for a variety of reasons, many of which are beyond our control. Additional information concerning risk factors relating to our business, prospects, and results are available in the Company’s filings with the Securities and Exchange Commission, including the Company’s Form 10-Q for the quarter ended March 31, 2020 which we plan to file later today, and any other public filings and press releases.

Additionally, to the extent we discuss non-GAAP measures such as adjusted EBITDAX and adjusted EBITDA, please see our earnings press release for the calculation of these measures and the GAAP reconciliations.

Additional information can be found on Riviera Resources’ website at www.RivieraResourcesInc.com in the Investor section. I will now turn the call over to David Rottino, Riviera’s President and CEO.

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David Rottino

Introduction

Thanks Paula, and good morning everyone. We appreciate you taking time today to join us for the review of Riviera’s first quarter 2020 results. Joining us today are Dan Furbee, Executive Vice President and Chief Operating Officer, and Jim Frew, Riviera’s Executive Vice President and Chief Financial Officer. On our call today, I will provide an overview of Riviera’s strategic initiatives, cost reductions, first quarter results, and Blue Mountain Midstream business. I will then turn the call over to Jim to discuss financial results.

Strategic

Riviera continues to deliver on our commitment to drive shareholder value through efficiently managing our assets, remaining focused on capital discipline and returning capital to shareholders. Since our last quarterly call, we closed four transactions generating proceeds of approximately $69 million. This is a great outcome, considering we were able to accomplish this with little to no adjustment to the original contract prices, especially in light of the difficult market environment we experienced in the first quarter.

As difficult as this environment has been we have actually been able to continue to return capital to shareholders as a result of our strong balance sheet. We have returned or announced approximately $107 million of capital to investors through a $1.00 per share cash distribution paid in April, a $0.75 per share cash distribution payable in May, and open market share repurchases. In addition, we paid a $4.25 per share cash distribution to shareholders in December 2019, returning another approximately $250 million.

Riviera also remains committed to reducing costs to optimally manage the business during this market downturn. To that end, we announced the consolidation of management of Blue Mountain within the Company’s existing executive management team, while continuing to maintain separate capital structures for each entity. This action combined with other cost cutting initiatives will lower expected general and administrative costs by approximately 43% on a run rate basis. By fourth quarter we expect annualized G&A costs to be approximately $26MM for Blue Mountain and Riviera Upstream combined.

With our continued focus on reducing costs, the Company has also decided to suspend its North Louisiana operated drilling program, reducing 2020 capital by $21 million. However, as natural gas prices continue to improve, we retain the option to re-initiate a drilling program later this year.

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Finally, the operating team has been extremely focused on lowering lease operating expenses. The Company has taken several proactive steps to significantly reduce these costs, including a reduction in workforce, optimizing compression, reducing workover projects, and negotiating lower overall service costs. As a result, the company expects Riviera Upstream’s LOE to be 25% lower this year versus our prior guidance.

First Quarter Update

Turning now to our first quarter performance, with respect to our upstream assets, we have met or exceeded production and adjusted EBITDAX guidance every quarter since our formation in 2018. We have focused on lowering operating expenses and we have significantly reduced G&A. We have judiciously managed capital expenditures in 2020 by suspending the North Louisiana operated drilling program, with minimal impact to full year adjusted EBITDAX. Because the acreage is held by production, the Company has the flexibility to drill at a later date without the risk of losing its current leases. However, we remain encouraged by the reliability and results of development locations in the Ruston field, that are expected to generate over 100% IRR’s at a $2.75/MMbtu gas price, and if prices do improve throughout the year, we will maintain the option to re-initiate the drilling program.

Blue Mountain

Turning to the Blue Mountain business, in the first quarter natural gas throughput on Blue Mountain’s gas system averaged 118 MMcf/d, relatively flat compared to the fourth quarter. During the first quarter, Blue Mountain continued tying in new wells and turned 14 wells to sales throughout the quarter.

With respect to the water business, we continue to make considerable progress on the buildout of the water gathering system. During the first quarter, Blue Mountain managed 3.7 million barrels of water in total, or approximately 40,600 barrels per day, up 39% from

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the fourth quarter. Of that total, the company gathered over 23,300 barrels per day on pipe (up 102% from fourth quarter 2019). With 57% of managed water on Blue Mountain’s pipe, Blue Mountain exceeded its guidance range. Furthermore, Blue Mountain completed construction of its third wholly owned and operated salt water disposal well.

Blue Mountain began construction of its crude oil gathering system in October 2019. The initial segments on the South system were placed in service on February 1,2020 and the initial segments on the North system were placed in service on March 2, 2020.

Starting in April, due to consistently low commodity prices, certain producers have elected to curtail production. As a result, Blue Mountain expects to see lower second quarter throughput at its gas processing plant versus the prior quarter. At the end of April, natural gas throughput was approximately 80 mmcf/d. Given the dynamic environment, the Company has chosen not to provide second quarter guidance for Blue Mountain.

Finally, I would like to take a moment to thank all our employees for their tremendous efforts over the last couple of months as we have found productive ways to implement social distancing including in many cases working remotely. In the face of all the distractions and challenges we have confronted during the quarter we continue to find ways to meet or exceed expectations. So, Thank you!

With that, I will turn the call over to Jim to discuss the financials in more detail.

Jim Frew

Thanks, Dave. Before opening the call up for Q&A, I’d like to discuss the following items: 1) first quarter performance, 2) balance sheet and liquidity, 3) return of capital to shareholders, and 4) 2020 upstream guidance.

First Quarter Performance

We had another solid quarter with production averaging 72 MMcfe/d. This was above the midpoint of our guidance range. Operating costs came in at the lower range of our guidance, driven by much lower lease operating expenses partially offset by higher transportation costs. For the quarter, adjusted EBITDAX came in above guidance while capital expenditures were in-line with guidance.

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In the first quarter of 2020, total oil, natural gas and NGL revenues were approximately $15 million. Of that approximately 64% of the revenue was from natural gas sales, 29% was from the oil sales, and the remaining 7% was from the sales of NGLs.

With respect to costs, operating expenses for the first quarter were approximately $8 million, which was at the lower end of the guidance range. General and administrative costs, excluding share-based compensation and severance costs, were approximately $11.4 million in the first quarter. Of that approximately $8.5 million was incurred by the Upstream business, and the remaining $2.9 million was incurred by Blue Mountain. With consolidation of Blue Mountain’s management team with the existing Riviera management team, and other cost reduction initiatives, the company expects by fourth quarter 2020, General and Administrative expenses, excluding share-based compensation and severance expenses, will be approximately $6.5 million. This represents a 43% decrease from the first quarter 2020.

In the first quarter, Riviera’s capital investment was approximately $14 million. Riviera Upstream capital was approximately $1 million while Blue Mountain invested approximately $13 million. The majority of Blue Mountain’s capital was invested on water and crude oil gathering pipelines. Capital expenditures were above prior guidance due to the acceleration of certain projects. Full year Blue Mountain capital is expected to be approximately $25 million, which is 11 % lower than prior guidance estimate.

Balance Sheet and Liquidity

With respect to the balance sheet and liquidity, Riviera and Blue Mountain have established separate credit facilities. As of March 31, 2020, there were no borrowings outstanding on Riviera’s revolving credit facility. Redetermination of the borrowing base under the Riviera Credit Facility occurs semi-annually. The Company expects the borrowing base will be reduced as a result of the spring redetermination. Currently, there are no borrowings under the Riviera Credit Facility.

Blue Mountain has established a separate credit facility with total borrowing commitments of up to $200 million. As of March 31, 2020, Blue Mountain had approximately $73 million drawn on its credit facility, and approximately $115 million of available borrowing capacity, inclusive of outstanding letters of credit, subject to covenant restrictions in the Blue Mountain Credit Facility.

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As of March 31, 2020, Riviera’s ending consolidated cash balance was approximately $165 million. Of that, approximately $155 million was attributable to the Upstream business, and approximately $10 million was held by Blue Mountain.

As of April 30, 2020, there were no borrowings outstanding on Riviera’s revolving credit facility and approximately $75 million drawn on Blue Mountain’s revolving credit facility.

Return of Capital to Shareholders

Thus far in 2020, the Company has returned or announced approximately $107 million of capital to shareholders including a $1.00 per share cash distribution paid in April 2020 totaling approximately $60 million, a $0.75 per share cash distribution payable on May 12, 2020, totaling approximately $45 million, and share repurchases. In 2019 the Company’s Board of Directors authorized an increase to the repurchase program up to a total of $150 million. As of April 30, 2020, the Company had approximately $22 million available for repurchase under its share repurchase authorization. As of April 30, 2020, Riviera had approximately 57.9 million shares outstanding.

Guidance

Looking ahead we have provided Upstream only guidance for the remainder of 2020. In our supplemental presentation posted to our website today, we highlight the full year 2020 upstream guidance taking into consideration the recent cost reduction initiatives that have been taken to lower general and administrative, operating, and capital expenditures.

In 2020, the upstream business expects production will average 46 to 50 MMcfe/d. Based on the plan, the business will generate $4 million of adjusted EBITDA, including expected severance costs of $2 to $4 million. Of note, second quarter adjusted EBITDA is expected to be negative. This reflects depressed commodity prices for the quarter, higher G&A due to costs associated with managing assets that we are transitioning to buyers and anticipated severance costs. In the second half of the year, we expect the upstream business to generate positive cash flow as we continue to focus on reducing costs to better fit the remaining upstream assets owned.

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With respect to capital, the combined upstream and midstream businesses expect to invest $28 million in 2020. Approximately $3 million will be applied to upstream activity while Blue Mountain expects to invest $25 million throughout the year. Taken together, the Company has reduced its capital program by $25MM, or 47%, versus prior guidance.

In closing, our assets performed well in the first quarter and our balance sheet allows us flexibility. Moving forward, we continue to look for opportunities to maximize shareholder value, and we are committed to finding ways to return capital to shareholders. With that, I will hand it over to the operator to open this call up for questions.

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Exhibit 99.3

RIVIERA RESOURCES, INC.

UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL INFORMATION

On November 22, 2019, Riviera Resources, Inc., (“Riviera” or the “Company”) completed the sale of its interests in remaining properties located in the Hugoton Basin (the “Hugoton Basin Assets Sale”) to Scout Energy Group V, LP (the “Buyer”) under a Purchase and Sale Agreement dated August 28, 2019, for a purchase price of approximately $286 million. During the year ended December 31, 2019, the Company recorded a noncash impairment charge of approximately $100 million to reduce the carrying value of these assets to fair value.

In connection with the Hugoton Basin Assets Sale, the Buyer also acquired the Company’s interests in Mayzure, LLC (“Mayzure”), including a term overriding royalty interest in helium produced from certain oil and natural gas properties in the Hugoton Basin that Riviera contributed to Mayzure in March 2019 (the “VPP Interests”). On March 20, 2019, Mayzure issued 5.16% senior secured notes in the amount of approximately $82 million, due September 20, 2028, (the “Mayzure Notes”), which were secured by the VPP interests. Neither Riviera, nor any of its subsidiaries other than Mayzure, guaranteed the Mayzure Notes. In consideration for the distribution of the VPP Interests, Mayzure contributed the net proceeds from the issuance of the Mayzure Notes to Riviera. Financing fees and expenses of approximately $3 million were incurred in connection with the Mayzure Notes and the Company made repayments of approximately $7 million.

The unaudited pro forma condensed consolidated statement of operations for the year ended December 31 2019, gives effect to the Hugoton Basin Assets Sale as if it had been completed as of January 1, 2019.

The following unaudited pro forma condensed consolidated financial statement was derived from the historical consolidated financial statements of the Company. The unaudited pro forma condensed consolidated financial statement is presented for informational and illustrative purposes only and is not necessarily indicative of the financial results that would have occurred if the transactions reflected therein had occurred on the date indicated, nor is such financial statement necessarily indicative of the Company’s results of operations in future periods. The pro forma condensed consolidated financial statement does not include realization of cost savings expected to result from such transaction. The assumptions and estimates underlying the adjustments to the unaudited pro forma condensed consolidated financial statement are described in the accompanying notes. The unaudited pro forma condensed consolidated financial information should also be read in conjunction with the Company’s historical financial statements and the notes thereto included in its Annual Report on Form 10-K for the year ended December 31, 2019.

The preparation of the unaudited pro forma condensed consolidated financial information is based on financial statements prepared in accordance with accounting principles generally accepted in the United States of America. These principles require the use of estimates that effect the reported amounts of revenues and expenses. Actual results could differ from those estimates.

The unaudited pro forma condensed consolidated financial information does not purport to represent what the actual results of operations would have been had the transaction occurred on the date assumed, nor is it necessarily indicative of the Company’s future operating results. However, the pro forma adjustments reflected in the accompanying unaudited pro forma condensed financial information reflect estimates and assumptions that Company management believes to be reasonable.

RIVIERA RESOURCES, INC.

UNAUDITED PRO FORMA CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS

YEAR ENDED DECEMBER 31, 2019

(in thousands, except per share amounts)

The accompanying notes are an integral part of these unaudited pro forma condensed consolidated financial statements.

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RIVIERA RESOURCES, INC.

NOTES TO UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Historical Riviera Resources, Inc.

These amounts represent the Company’s condensed consolidated historical statement of operations. Amounts for the year ended December 31, 2019, were derived from the Company’s Annual Report on Form 10-K for the year ended December 31, 2019.

The historical condensed consolidated statement of operations has been adjusted in the unaudited pro forma condensed consolidated statement of operations to give effect to pro forma events that are (i) directly attributable to the transaction, (ii) factually supportable and (iii) expected to have a continuing impact on results of operations.

Pro Forma Adjustments

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