Form 8-K

8-K — Ribbon Communications Inc.

Accession: 0001104659-26-050356

Filed: 2026-04-28

Period: 2026-04-28

CIK: 0001708055

SIC: 7373 (SERVICES-COMPUTER INTEGRATED SYSTEMS DESIGN)

Item: Results of Operations and Financial Condition

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Financial Statements and Exhibits

Documents

8-K — tm2612891d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2612891d1_ex99-1.htm)

EX-99.2 — EXHIBIT 99.2 (tm2612891d1_ex99-2.htm)

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8-K — FORM 8-K

8-K (Primary)

Filename: tm2612891d1_8k.htm · Sequence: 1

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0001708055

2026-04-28

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities

Exchange Act of 1934

April 28, 2026

Date

of Report (Date of earliest event reported)

RIBBON COMMUNICATIONS INC.

(Exact Name of Registrant as Specified in its Charter)

Delaware

001-38267

82-1669692

(State or Other Jurisdiction

of Incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

6500 Chase Oaks Blvd., Suite 100, Plano, TX

75023

(Address of Principal Executive Offices) (Zip Code)

(978) 614-8100

(Registrant’s telephone number, including

area code)

N/A

(Former Name or Former Address, if Changed Since

Last Report)

Check the appropriate box below if the Form 8-K

filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see

General Instruction A.2. below):

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b)

of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, par value $0.0001

RBBN

The Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging

growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities

Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging

growth company ¨

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. ¨

Item 2.02.

Results of Operations and Financial

Condition.

The information in this Item 2.02 of this Current

Report on Form 8-K (the "Current Report"), including Exhibit 99.1 attached hereto, shall not be deemed “filed”

for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), otherwise subject

to the liabilities of that Section or incorporated by reference in any filing under the Securities Act of 1933, as amended (the "Securities

Act"), or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

On April 28, 2026, Ribbon Communications Inc.

(the "Company") issued a press release reporting financial information for the quarter ended March 31, 2026, a copy of

which is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

Item 5.02.

Departure of Directors or Certain Officers; Election

of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

(b) Departure of Certain Officers

On April 28, 2026, Ribbon Communications Inc. (the “Company”)

announced that John Townsend, Executive Vice President, Chief Financial Officer of the Company, has notified the Company that he is resigning

effective April 30, 2026 to pursue another professional opportunity. Mr. Townsend’s departure is not related to any

disagreement with the Company relating to its operations, policies or practices.

On April 28, 2026, in connection with Mr. Townsend’s

departure, the Company announced that it is promoting Eric “Rick” Marmurek to the position of Executive Vice President, Chief

Financial Officer and Chief Accounting Officer of the Company effective May 1, 2026. Mr. Marmurek, CPA, age 60, has served as

the Company’s Senior Vice President and Chief Accounting Officer since 2018 and was promoted to Deputy Chief Financial Officer

and Chief Accounting Officer in October 2024. Mr. Marmurek has over 35 years of financial experience. He has been

with the Company and its predecessor companies for more than 15 years. Prior to joining the Company, he spent 10 years doing

tax-related work for Nokia. He started his career in public accounting with Coopers and Lybrand. Mr. Marmurek earned

an accounting degree from the University of Texas at Austin and a Master of Business Administration from Southern Methodist University.

Mr. Marmurek’s annual compensation consists of a base salary

of $475,000, a target bonus of 75% of his base salary, and he is eligible for annual equity grants. Mr. Marmurek’s compensatory

arrangements are subject to review and adjustment in accordance with the Company’s applicable practices and policies.

There is no arrangement or understanding between Mr. Marmurek

and any other person pursuant to which Mr. Marmurek was appointed as Executive Vice President, Chief Financial Officer and Chief

Accounting Officer. There are no family relationships between Mr. Marmurek and any director or executive officer of the Company,

and he has no direct or indirect material interest in any transaction required to be disclosed pursuant to Item 404(a) of Regulation S-K.

On April 28, 2026, the Company issued a press release announcing

Mr. Marmurek’s appointment. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

Item 9.01. Financial Statements and Exhibits.

(d)

Exhibits.

99.1

Press Release, dated April 28, 2026, regarding preliminary financial results.

99.2

Press Release, dated April 28, 2026, regarding Rick Marmurek.

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements

of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto

duly authorized.

Date: April 28, 2026

Ribbon Communications Inc.

By:

/s/ Patrick Macken

Name:

Patrick W. Macken

Title:

Executive Vice President, Chief Legal Officer and Secretary

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2612891d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

Ribbon Communications Inc. Reports

First Quarter 2026 Financial Results

Growing Demand Increases Confidence in Sequential

and 2nd Half 2026 Growth

Momentum Building in New Markets including AIOps

and Data Center Interconnect

First Quarter Revenue in Line with Expectations

PLANO, Texas – Ribbon Communications Inc. (Nasdaq:

RBBN), a global leader in real-time communications technology and IP optical networking solutions, today announced its financial results

for the first quarter of 2026. Ribbon Communications is dedicated to assisting the world's largest service providers, enterprises, and

critical infrastructure operators in modernizing and safeguarding their networks and services.

First Quarter 2026 Highlights

Financial

Results1:

· Revenue was $163 million, compared to $181 million for the first quarter

of 2025

· GAAP Operating Loss was ($32) million, compared to ($20) million for the

first quarter of 2025

· Non-GAAP Adjusted EBITDA was ($8) million, compared to $6 million for the

first quarter of 2025

· GAAP Gross Margin was 42.9%, compared to 45.4% for the first quarter of 2025

· Non-GAAP Gross Margin was 45.8%, compared to 48.6% for the first quarter

of 2025

“We remain confident in the underlying demand environment

and continue to expect meaningful second-half growth across multiple end markets including voice transformation projects with U.S.

Service Providers and Federal agencies, and growing IP and Optical deployments in the U.S. and EMEA regions, with significant

improvement beginning in the second quarter,” stated Bruce McClelland, President and Chief Executive Officer of Ribbon

Communications. “Revenue in the first quarter was in line with expectations and reflected the timing dynamics we outlined

earlier this year. While margins were pressured by a slower deployment pace with key U.S. Tier 1 Service Providers and higher sales

in India, we expect margin expansion as revenue increases

throughout the year.”

Mr. McClelland continued, “We were particularly

pleased by several new Data Center Interconnect wins in the first quarter, as well as multiple new secure private optical network

awards supporting major energy producers and distributors in multiple countries. Importantly, we are gaining traction with our

Ribbon AcumenTM AIOps platform with several new customer engagements and a growing pipeline of POCs. Furthermore, we

believe our recent Strategic Collaboration Agreement with Amazon Web Services further strengthens our leadership position in

cloud-native communications infrastructure to enable Agentic and AI voice capabilities.”

John Townsend, Chief Financial Officer of Ribbon Communications,

remarked, “We continue to make deliberate investments to support our expected second half revenue growth including maintaining

higher professional services capacity and retaining highly skilled resources. Notwithstanding this, we are staying focused on

controlling expenses and driving efficiencies, helping mitigate currency headwinds.”

Three months ended

March 31,

In millions, except per share amounts

2026

2025

GAAP Revenue

$ 163

$ 181

GAAP Net income (loss)

$ (34 )

$ (26 )

Non-GAAP Net income (loss)

$ (8 )

$ (5 )

Non-GAAP Adjusted EBITDA

$ (8 )

$ 6

GAAP diluted earnings (loss) per share

$ (0.20 )

$ (0.15 )

Non-GAAP diluted earnings (loss) per share

$ (0.05 )

$ (0.03 )

Weighted average shares outstanding basic

176

Weighted average shares outstanding diluted

178

180

1 Please see the reconciliations of non-GAAP financial measures

to the most directly comparable GAAP measures and additional information about non-GAAP measures in the section entitled “Discussion

of Non-GAAP Financial Measures” in the attached schedules.

Business Highlights:

· Ribbon

Provides Edge Solutions for Salt’s Enterprise Voice Expansion

· Ribbon

and AWS Transform Cloud Deployment for Service Providers and Enterprises

Business Outlook2

For the second quarter of 2026, the Company projects revenue of $185

million to $195 million. Non-GAAP gross margin is projected in a range of 49% to 50%. Adjusted EBITDA is projected in a range of $9 million

to $14 million.

The Company’s outlook is based on current indications for its

business, which are subject to change.

2 GAAP earnings guidance is not provided. Please see the

reconciliations of non-GAAP financial measures to the most directly comparable GAAP measures and additional information about the non-GAAP

measures in the section entitled “Discussion of Non-GAAP Financial Measures” in the attached schedules.

Upcoming Conference Schedule

· May 12, 2026:                    21st Annual Needham Technology, Media, &

Consumer 1x1 Conference

· May 21, 2026:                    B. Riley Securities 26th Annual Investor Conference

· June 17, 2026:                    TD Cowen and CEO Summit Inaugural Disruptive Technology

Summit

· June 23, 2026:                    Northland Growth Conference

Conference Call and Webcast Information

Ribbon Communications will host a conference call to discuss the Company’s

financial results at 4:30 p.m. ET on Tuesday, April 28, 2026.

Dial-in Information:

US/Canada: 877-407-2991

International: 201-389-0925

Instant Telephone Access: Call me™

A live (listen-only) webcast and replay will be available on the Company’s

Investor Relations website at investors.ribboncommunications.com.

Investor Contact

+1 (978) 614-8050

ir@rbbn.com

Media Contact

Catherine Berthier

+1 (646) 741-1974

cberthier@rbbn.com

About Ribbon

Ribbon Communications (Nasdaq: RBBN) is a global provider of voice communications software, IP routing, and optical networking

to mobile and wireline service providers, enterprises, critical infrastructure and defense sectors. We support our customers’ Path

to Autonomous Networks by leveraging the latest AIOps automation platforms and Agentic AI technologies, helping them deliver better customer

experiences, reduce operational costs, and achieve sustainable growth.

To learn more about Ribbon visit rbbn.com.

Important Information Regarding Forward-Looking Statements

This release contains “forward-looking statements” within

the meaning of the U.S. Private Securities Litigation Reform Act of 1995, which are subject to a number of risks and uncertainties. All

statements other than statements of historical facts contained in this release, including without limitation, statements regarding Company’s

projected financial results for the second quarter of 2026 and beyond; expected customer spend and timing; beliefs about the Company’s

business strategy, including new product introductions such as the Acumen AIOps platform; beliefs about the accelerating adoption of AI

and the shift towards autonomous networking; and the timing of customer network transformation projects, are forward-looking statements.

Without limiting the foregoing, the words “anticipates”, “believes”, “could”, “estimates”,

“expects”, “expectations”, “intends”, “may”, “plans”, “projects”

and other similar language, whether in the negative or affirmative, are intended to identify forward-looking statements, although not

all forward-looking statements contain these identifying words.

Forward-looking statements are based on the Company’s current

expectations and assumptions regarding its business, the economy and other future conditions. Because forward-looking statements relate

to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are unknown and/or difficult to predict

and that may cause the Company’s actual results, performance or achievements to be materially different from those expressed or

implied by the forward-looking statements. Such risks and uncertainties include, but are not limited to, unpredictable fluctuations in

quarterly revenue and operating results; the impact of restructuring and cost-containment activities; increases in tariffs, trade restrictions

or taxes on our products; supply chain disruptions resulting from component availability and/or geopolitical instabilities and disputes

(including those related to the wars in the Middle East and Ukraine); other impacts from the wars in the Middle East and Ukraine and related

economic volatility and uncertainty resulting therefrom; the impact of military call-ups of our employees in Israel; material litigation;

the impact of fluctuations in interest rates; material cybersecurity and data intrusion incidents, including any security breaches resulting

in the theft, transfer, or unauthorized disclosure of customer, employee, or company information; our ability to comply with applicable

domestic and foreign information security and privacy laws, regulations and technology platform rules or other obligations related

to data privacy and security; failure to compete successfully against telecommunications equipment and networking companies; failure to

grow our customer base or generate recurring business from our existing customers; credit risks; the timing of customer purchasing decisions

and our recognition of revenues; macroeconomic conditions, including inflation; our ability to adapt to rapid technological and market

changes; our ability to generate positive returns on our research and development; our ability to protect our intellectual property rights

and obtain necessary licenses; our ability to maintain partner, reseller, distribution and vendor support and supply relationships; the

potential for defects in our products; risks related to the terms of our credit agreement; higher risks in international operations and

markets; currency fluctuations; unanticipated adverse changes in legal, regulatory or tax laws; future accounting pronouncements or changes

in our accounting policies; and/or failure or circumvention of our controls and procedures. We therefore caution you against relying on

any of these forward-looking statements.

These factors are not intended to be an all-encompassing list of risks

and uncertainties that may affect the Company's business and results from operations. Additional information regarding these and other

factors can be found in the Company's reports filed with the Securities and Exchange Commission, including, without limitation, its Form 10-K

for the year ended December 31, 2025. Any forward-looking statement made by the Company in this release speaks only as of the date

on which this release was first issued. The Company undertakes no obligation to update any forward-looking statement publicly or otherwise,

whether as a result of new information, future developments or otherwise, except as required by law.

Discussion of Non-GAAP Financial

Measures

The Company’s management uses several different financial measures,

both GAAP and non-GAAP, in analyzing and assessing the overall performance of its business, making operating decisions, planning and forecasting

future periods, and determining payments under compensation programs. The Company considers the use of non-GAAP financial measures helpful

in assessing the core performance of its continuing operations and when planning and forecasting future periods. The Company’s annual

financial plan is prepared on a non-GAAP basis and is approved by its board of directors. In addition, budgeting and forecasting for revenue

and expenses are conducted on a non-GAAP basis, and actual results on a non-GAAP basis are assessed against the annual financial plan.

The Company defines continuing operations as the ongoing results of its business adjusted for certain expenses and credits, as described

below. The Company believes that providing non-GAAP information to investors allows them to view the Company's financial results in the

way its management views them and helps investors to better understand the Company’s core financial and operating performance and

evaluate the efficacy of the methodology and information used by its management to evaluate and measure such performance.

While the Company’s management uses non-GAAP financial measures

as tools to enhance its understanding of certain aspects of the Company’s financial performance, management does not consider these

measures to be a substitute for, or superior to, GAAP measures. In addition, the Company’s presentations of these measures may not

be comparable to similarly titled measures used by other companies. These non-GAAP financial measures should not be considered alternatives

for, or in isolation from, the financial information prepared and presented in accordance with GAAP. Investors are cautioned that there

are material limitations associated with the use of non-GAAP financial measures. In particular, many of the adjustments to the Company’s

financial measures reflect the exclusion of items that are recurring and will be reflected in its financial results for the foreseeable

future.

Stock-Based Compensation

The expense related to stock-based awards is generally not controllable

in the short-term and can vary significantly based on the timing, size and nature of awards granted. The Company believes that presenting

non-GAAP operating results that exclude stock-based compensation provides investors with visibility and insight into its management’s

method of analysis and its core operating performance.

Amortization of Acquired Technology (including software licenses);

Amortization of Acquired Intangible Assets

Amortization amounts are inconsistent in frequency and amount and are

significantly impacted by the timing and size of acquisitions. Amortization of acquired technology is reported separately within Cost

of revenue and Amortization of acquired intangible assets is reported separately within Operating expenses. These items are reported collectively

as Amortization of acquired intangible assets in the accompanying reconciliations of non-GAAP and GAAP financial measures. The Company

believes that excluding non-cash amortization of these intangible assets facilitates the comparison of its financial results to its historical

operating results and to other companies in its industry as if the acquired intangible assets had been developed internally rather than

acquired.

Litigation Costs

In connection with certain ongoing litigation where Ribbon is the defendant

(as described in the Company's Commitments and Contingencies footnotes in its Form 10-Qs and Form 10-Ks filed with the SEC,

the Company has incurred litigation costs beginning in 2023. These costs are included as a component of general and administrative expense.

The Company believes that such costs are not part of its core business or ongoing operations, are unplanned, and generally are not within

its control. Accordingly, the Company believes that excluding litigation costs related to these specific legal matters facilitates the

comparison of the Company's financial results to its historical operating results and to other companies in its industry.

Cybersecurity Incident

The Company has recorded expenses associated with responding to and

remediating a cybersecurity incident, including costs for external legal services, cybersecurity experts, and IT restoration activities.

The Company believes that excluding these expenses facilitates the comparison of its financial results to its historical operating performance

and to other companies in its industry, as these costs are non-recurring in nature and are not associated with future revenue streams

or ongoing operational benefits.

Acquisition-, Disposal- and Integration-Related

The Company considers certain acquisition-, disposal- and integration-related

costs to be unrelated to the organic continuing operations of the Company and its acquired businesses. Such costs are generally not relevant

to assessing or estimating the long-term performance of the acquired assets. In 2025, the Company recorded expense for legal and professional

fees associated with contemplated corporate development activities. The Company excludes such acquisition-, disposal- and integration-related

costs to allow more accurate comparisons of its financial results to its historical operations and the financial results of less acquisitive

peer companies and allows management and investors to consider the ongoing operations of the business both with and without such expenses.

Restructuring and Related

The Company has recorded restructuring and related expense to streamline

operations and reduce operating costs by closing and consolidating certain facilities and reducing its worldwide workforce. The Company

believes that excluding restructuring and related expense facilitates the comparison of its financial results to its historical operating

results and to other companies in its industry, as there are no future revenue streams or other benefits associated with these costs.

Preferred Stock and Warrant Liability Mark-to-Market Adjustment

The Company recorded adjustments to the fair value of its Series A

Preferred Stock and Warrants to purchase shares of the Company’s common stock in Other (expense) income, net. Both of these instruments

were issued in March 2023 in connection with the Company’s private placement and have been classified as liabilities and marked

to market each reporting period until the Series A Preferred Stock was fully redeemed on June 25, 2024. The Warrant liability

remains outstanding and will continue to be marked to market each reporting period. The Company excluded these gains and losses from the

change in the fair value of these liabilities because it believes that such gains or losses were not part of its core business or ongoing

operations.

Tax Effect of Non-GAAP Adjustments

The Non-GAAP income tax provision is presented based on an estimated

tax rate applied against forecasted annual non-GAAP income. The Company computes its non-GAAP estimated tax rate using its estimated GAAP

annual effective tax rate for the period and adjusting for the tax effect of pre-tax non-GAAP adjustments. The Company computes a

single annual non-GAAP rate for the Company and applying that rate (rather than multiple rates by jurisdiction) to its consolidated quarterly

results. The Company expects that this methodology will provide a consistent rate throughout the year and allow investors to better understand

the impact of income taxes on its results. Due to the methodology applied to its estimated annual tax rate, the Company’s estimated

tax rate on non-GAAP income will differ from its GAAP tax rate and from its actual tax liabilities.

Adjusted EBITDA

The Company uses Adjusted EBITDA as a supplemental measure to review

and assess its performance. The Company calculates Adjusted EBITDA by excluding from income (loss) from operations: depreciation; stock-based

compensation; amortization of acquired intangible assets; certain litigation costs; expenses related to cybersecurity incidents; acquisition-,

disposal- and integration-related expense; and restructuring and related expense. In general, the Company excludes the expenses that it

considers to be non-cash and/or not a part of its ongoing operations. The Company may exclude other items in the future that have those

characteristics. Adjusted EBITDA is a non-GAAP financial measure that is used by the investing community for comparative and valuation

purposes. The Company discloses this metric to support and facilitate dialogue with research analysts and investors. Other companies may

calculate Adjusted EBITDA differently than the Company does, limiting its usefulness as a comparative measure.

RIBBON COMMUNICATIONS INC.

Consolidated Statements of Operations

(in thousands, except percentages and per share

amounts)

(unaudited)

Three months ended

March 31,

December 31

March 31,

2026

2025

Revenue:

Product

$ 68,114

$ 127,560

$ 81,991

Service

94,492

99,763

99,288

Total revenue

162,606

227,323

181,279

Cost of revenue:

Product

49,425

62,571

57,893

Service

38,928

39,067

35,628

Amortization of acquired technology

4,562

4,622

5,388

Total cost of revenue

92,915

106,260

98,909

Gross profit

69,691

121,063

82,370

Gross margin

42.9 %

53.3 %

45.4 %

Operating expenses:

Research and development

44,445

44,714

43,568

Sales and marketing

32,269

35,688

31,788

General and administrative

16,978

16,113

15,128

Amortization of acquired intangible assets

5,656

5,786

6,155

Restructuring and related

2,038

9,465

5,341

Total operating expenses

101,386

111,766

101,980

Income (loss) from operations

(31,695 )

9,297

(19,610 )

Interest expense, net

(9,756 )

(10,928 )

(10,500 )

Other (expense) income, net

514

1,390

3,129

Income (loss) before income taxes

(40,937 )

(241 )

(26,981 )

Income tax benefit (provision)

6,448

89,306

754

Net income (loss)

$ (34,489 )

$ 89,065

$ (26,227 )

Earnings (loss) per share:

Basic

$ (0.20 )

$ 0.51

$ (0.15 )

Diluted

$ (0.20 )

$ 0.50

$ (0.15 )

Weighted average shares used to compute earnings (loss) per share:

Basic

175,661

175,704

175,719

Diluted

175,661

178,724

175,719

RIBBON COMMUNICATIONS INC.

Consolidated Balance Sheets

(in thousands)

(unaudited)

March 31,

December 31,

2026

2025

Assets

Current assets:

Cash and cash equivalents

$ 67,554

$ 96,405

Restricted cash

2,045

1,726

Accounts receivable, net

204,058

231,885

Inventory

81,463

78,806

Other current assets

53,379

45,663

Total current assets

408,499

454,485

Property and equipment, net

64,077

65,559

Intangible assets, net

134,233

143,344

Goodwill

300,892

Deferred income taxes

181,834

174,318

Operating lease right-of-use assets

44,010

46,240

Other assets

26,157

27,417

$ 1,159,702

$ 1,212,255

Liabilities and Stockholders' Equity

Current liabilities:

Current portion of term debt

$ 8,750

Accounts payable

77,293

79,840

Accrued expenses and other

77,890

90,759

Operating lease liabilities

11,601

11,699

Warrant liability

682

Deferred revenue

122,619

124,425

Total current liabilities

298,835

315,473

Long-term debt, net of current

322,975

324,525

Warrant liability

1,919

Operating lease liabilities, net of current

57,042

60,159

Deferred revenue, net of current

32,423

31,654

Deferred income taxes

5,728

Other long-term liabilities

23,597

23,803

Total liabilities

740,600

763,261

Commitments and contingencies

Stockholders' equity:

Common stock

Additional paid-in capital

1,981,988

1,976,958

Accumulated deficit

(1,569,038 )

(1,534,549 )

Accumulated other comprehensive income

6,134

6,567

Total stockholders' equity

419,102

448,994

$ 1,159,702

$ 1,212,255

RIBBON COMMUNICATIONS INC.

Consolidated Statements of Cash Flows

(in thousands)

(unaudited)

Three months ended

March 31,

2026

2025

Cash flows from operating activities:

Net income (loss)

$ (34,489 )

$ (26,227 )

Adjustments to reconcile net income (loss) to cash flows (used in) provided by operating activities:

Depreciation and amortization of property and equipment

4,460

3,469

Amortization of intangible assets

10,218

11,543

Amortization of debt issuance costs and original issue discount

701

Stock-based compensation

5,957

4,298

Deferred income taxes

(7,628 )

(4,628 )

Change in fair value of warrant liability

(1,237 )

(1,735 )

Foreign currency exchange (gains) losses

1,173

(1,328 )

Changes in operating assets and liabilities:

Accounts receivable

27,233

29,459

Inventory

(4,600 )

(1,546 )

Other operating assets

(2,801 )

(5,578 )

Accounts payable

(3,389 )

(2,184 )

Accrued expenses and other long-term liabilities

(16,558 )

(9,631 )

Deferred revenue

(1,036 )

(148 )

Net cash (used in) provided by operating activities

(21,996 )

(3,535 )

Cash flows from investing activities:

Purchases of property and equipment

(3,072 )

(12,149 )

Net cash (used in) provided by investing activities

(3,072 )

(12,149 )

Cash flows from financing activities:

Principal payments of term debt

(2,187 )

(875 )

Proceeds from the exercise of stock options

Payment of tax obligations related to vested stock awards and units

(103 )

(938 )

Repurchase of common stock

(824 )

Net cash (used in) provided by financing activities

(3,114 )

(1,812 )

Effect of exchange rate changes on cash and cash equivalents

(350 )

831

Net (decrease) increase in cash and cash equivalents

(28,532 )

(16,665 )

Cash, cash equivalents and restricted cash, beginning of year

98,131

90,479

Cash, cash equivalents and restricted cash, end of period

$ 69,599

$ 73,814

RIBBON COMMUNICATIONS INC.

Supplemental Information

(in thousands)

(unaudited)

The following tables provide the details of stock-based compensation

included as components of other line items in the Company's Consolidated Statements of Operations and the line items in which these amounts

are reported.

Three months ended

March 31,

December 31

March 31,

2026

2025

Stock-based compensation

Cost of revenue - product

$ 43

$ 66

Cost of revenue - service

161

165

286

Cost of revenue

204

208

352

Research and development

477

436

725

Sales and marketing

1,130

915

1,173

General and administrative

4,146

3,228

2,048

Operating expense

5,753

4,579

3,946

Total stock-based compensation

$ 5,957

$ 4,787

$ 4,298

RIBBON COMMUNICATIONS INC.

Reconciliation of Non-GAAP and GAAP Financial Measures

(in thousands, except per share amounts)

(unaudited)

Three months ended

March 31,

December 31

March 31,

2026

2025

GAAP Gross margin

42.9 %

53.3 %

45.4 %

Stock-based compensation

0.1 %

0.2 %

Amortization of acquired technology

2.8 %

2.0 %

3.0 %

Non-GAAP Gross margin

45.8 %

55.4 %

48.6 %

GAAP Net income (loss)

$ (34,489 )

$ 89,065

$ (26,227 )

Stock-based compensation

5,957

4,787

4,298

Amortization of intangible assets

10,218

10,408

11,543

Litigation costs

744

973

800

Cybersecurity incident

600

Restructuring and related

2,038

9,465

5,341

Preferred stock and warrant liability mark-to-market adjustment

(1,237 )

(3,184 )

(1,735 )

Tax effect of non-GAAP adjustments

8,412

(5,964 )

1,401

Non-GAAP Net income (loss)

$ (8,357 )

$ 106,150

$ (4,579 )

GAAP Diluted earnings (loss) per share

$ (0.20 )

$ 0.50

$ (0.15 )

Stock-based compensation

0.03

0.02

Amortization of intangible assets

0.06

0.07

Litigation costs

0.01

Cybersecurity incident

Restructuring and related

0.01

0.05

0.03

Preferred stock and warrant liability mark-to-market adjustment

(0.01 )

(0.02 )

(0.01 )

Tax effect of non-GAAP adjustments

0.05

(0.04 )

0.01

Non-GAAP Diluted earnings (loss) per share

$ (0.05 )

$ 0.59

$ (0.03 )

Weighted average shares used to compute diluted earnings (loss) per share

Shares used to compute GAAP

diluted earnings (loss) per share

175,661

178,724

175,719

Shares used to compute Non-GAAP

diluted earnings (loss) per share

175,661

178,724

175,719

GAAP Income (loss) from operations

$ (31,695 )

$ 9,297

$ (19,610 )

Depreciation

4,460

4,546

3,469

Stock-based compensation

5,957

4,787

4,298

Amortization of intangible assets

10,218

10,408

11,543

Litigation costs

744

973

800

Cybersecurity incident

600

Restructuring and related

2,038

9,465

5,341

Non-GAAP Adjusted EBITDA

$ (8,278 )

$ 40,076

$ 5,841

* Less than $0.01 impact on earnings (loss) per share.

RIBBON COMMUNICATIONS INC.

Reconciliation of Non-GAAP and GAAP Financial Measures

(in thousands)

(unaudited)

Trailing Twelve Months

March 31,

December 31

March 31,

2026

2025

GAAP Income (loss) from operations

$ (15,409 )

$ (3,324 )

$ 10,748

Depreciation

17,719

16,728

13,614

Stock-based compensation

21,065

19,406

15,862

Amortization of intangible assets

42,868

44,193

49,148

Litigation costs

4,983

5,039

11,047

Cybersecurity incident

600

Acquisition-, disposal- and integration-related

4,337

Restructuring and related

16,355

19,658

12,436

Non-GAAP Adjusted EBITDA

$ 92,518

$ 106,637

$ 112,855

RIBBON COMMUNICATIONS INC.

Reconciliation of Non-GAAP and GAAP Financial Measures

- Outlook

(unaudited)

Three months ending

Year ending

June 30, 2026

December 31, 2026

Midpoint (1)

Range

Midpoint (1)

Range

Revenue ($ millions)

190

+/-

$5M

857.5

+/-

$17.5M

Gross margin:

GAAP outlook

47.2

50.9

Stock-based compensation

0.1

Amortization of acquired technology

2.2

2.0

Non-GAAP outlook

49.5

+/- 0.5%

53.0

+/- 0.5%

Adjusted EBITDA ($ millions):

GAAP income (loss) from operations

(13.0

)

22.2

Depreciation

4.5

18.3

Stock-based compensation

7.5

23.4

Amortization of intangible assets

9.8

39.1

Litigation costs

0.7

1.2

Restructuring and related

2.0

8.3

Non-GAAP outlook

11.5

+/- $2.5M

112.5

+/- $7.5M

(1) Q2 2026 and FY 2026 outlook represents the midpoint of the

expected ranges

EX-99.2 — EXHIBIT 99.2

EX-99.2

Filename: tm2612891d1_ex99-2.htm · Sequence: 3

Exhibit 99.2

Ribbon Communications Announces Promotion of

Rick Marmurek to Chief Financial Officer

FOR IMMEDIATE RELEASE: April 28, 2026.

PLANO, Texas – Ribbon Communications Inc. (Nasdaq:

RBBN), a global leader in real-time communications technology and IP optical networking solutions, today announced that Rick Marmurek,

Ribbon’s current Deputy Chief Financial Officer and Chief Accounting Officer, has been promoted to Executive Vice President, Chief

Financial Officer (“CFO”) and Chief Accounting Officer, effective May 1, 2026. He will succeed current CFO John Townsend

who will be leaving Ribbon effective April 30, 2026 to take another professional opportunity.

“Having worked closely with Rick over the last six years I am

thrilled to formally welcome him to our executive leadership team,” said Bruce McClelland, President and CEO of Ribbon. “Rick

has been a visible leader within the organization for more than a decade and has developed deep knowledge of our operations, the markets

in which we operate, and our customers. We believe Rick brings an unparalleled breadth of financial leadership, deep accounting expertise,

and knowledge of the business to support and advance Ribbon’s strategy. We wish John the best in his next opportunity.”

Mr. Marmurek, CPA, brings more than 35 years of financial

experience, including more than 15 years at Ribbon or its predecessor companies, where he has served as Senior Vice President,

Deputy CFO and Chief Accounting Officer since 2024. Mr. Marmurek has served as Senior Vice President and Chief Accounting

Officer since 2018. Prior to joining Ribbon, Mr. Marmurek was at Nokia for 10 years, specializing in tax-related work. He

started his career in public accounting with Coopers and Lybrand. Mr. Marmurek holds an accounting degree from the University

of Texas at Austin and a Master of Business Administration from Southern Methodist University.

Page 1 of 2

About Ribbon

Ribbon Communications (Nasdaq: RBBN) is a global provider of voice

communications software, IP routing, and optical networking to mobile and wireline service providers, enterprises, critical infrastructure

and defense sectors. We support our customers’ Path to Autonomous Networks by leveraging the latest AIOps automation platforms and

Agentic AI technologies, helping them deliver better customer experiences, reduce operational costs, and achieve sustainable growth.

To learn more about Ribbon, visit rbbn.com.

Investor Contact

+1 (978) 614-8050

ir@rbbn.com

Media Contact

Catherine Berthier

+1 (646) 741-1974

cberthier@rbbn.com

Page 2 of 2

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