Form 8-K

8-K — Ribbon Communications Inc.

Accession: 0001104659-26-043511

Filed: 2026-04-15

Period: 2026-04-15

CIK: 0001708055

SIC: 7373 (SERVICES-COMPUTER INTEGRATED SYSTEMS DESIGN)

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 — tm2611696d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2611696d1_ex99-1.htm)

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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 15, 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 5.02.

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Effective April 15, 2026, the Board of Directors (the “Board”)

of Ribbon Communications Inc. (the “Company”) elected to increase the size of the Board to nine members and appointed

Louis Silver to serve as a member of the Board until the Company’s 2026 Annual Meeting of Stockholders. It is expected that Mr.

Silver will be appointed to one or more of the standing committees of the Board when the Board next meets in May 2026.

Mr. Silver (age 72), currently serves as a corporate advisor and Managing

Director for Alba Capital S.A. and Wicklow Corp., private holding and investment companies. From 2005 to 2015, Mr. Silver was a Principal

at RP Capital UK Ltd., a multi-asset fund focused on liquid and illiquid investments in Eastern Europe, the Middle East and Africa. Mr.

Silver has over 25 years’ experience serving on boards at multiple private and public companies focused primarily on technology

investment. He currently serves on the Board of Directors of Ceva, Inc., a Nasdaq-listed company, where he is Chairman of the Audit Committee

and a member of the Compensation Committee.

The Board believes Mr. Silver is qualified to serve on the Board based

on his extensive background in strategic and investment advisory services, his legal and regulatory compliance experience, as well as

his experience serving as a director of numerous private and public companies, including many in the technology space.

Mr. Silver was appointed to the Board by the Swarth Stockholders (defined

below) pursuant to the Company’s First Amended and Restated Stockholders Agreement dated March 3, 2020 with JPMC Heritage Parent

LLC (“JPMC”), Heritage PE (OEP) III, L.P. (together with JPMC, entities affiliated with the Company’s largest

stockholder, JPMorgan Chase & Co. (collectively with any successor entities, the “JPM Stockholders”)), and ECI

Holding (Hungary) Kft. (as succeeded to by Swarth Investments Ltd., the “Swarth Stockholders”) There are no family

relationships between Mr. Silver and any other director or executive officer of the Company and there have been no transactions between

Mr. Silver and the Company in the last fiscal year, and none are currently proposed, that would require disclosure under Item 404(a) of

Regulation S-K.

In connection with his election as a director, Mr. Silver is entitled

to receive an annual retainer of $60,000 consistent with the Company’s Non-employee Director Compensation Plan (the “Director

Compensation Plan”). The retainer is payable quarterly and pro-rated for the partial year of service. In addition, Mr. Silver

is entitled to receive restricted share units (consistent with the Director Compensation Plan), which, subject to his continued service,

will vest on the earlier of (i) the first anniversary of the grant date of the award and (ii) the next annual shareholders meeting of

the Company which is at least 50 weeks after the immediately preceding year's annual stockholders meeting. The number of shares eligible

to be received upon the vesting of the restricted share units will have a value (based on the closing price of the Company’s common

stock on the date of grant) equal to $170,000 pro-rated for the portion of the year that has elapsed since the Company’s 2025 Annual

Meeting of Stockholders. In addition, Mr. Silver will receive additional annual retainers for his expected service on one or more standing

committees of the Board when appointed. In accordance with the Company’s customary practice, the Company also expects to enter into

its standard form of indemnification agreement with Mr. Silver, which agreement is filed as Exhibit 10.5 to the Company’s Annual

Report on Form 10-K filed with the SEC on March 8, 2018.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

99.1 Press Release of Ribbon Communications Inc., dated April 15, 2026.

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 15, 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: tm2611696d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

Ribbon Appoints

Louis Silver to its Board of Directors

FOR IMMEDIATE RELEASE: April 15, 2026

Plano, TX – Ribbon Communications Inc.

(Nasdaq: RBBN), a global leader in real-time communications technology and IP optical networking solutions, today announced the appointment

of Louis Silver to its Board of Directors.

“We are pleased to have Lou join the Board” said Shaul

Shani, Chairman of the Board at Ribbon. “Lou has a long history of working with technology companies and brings significant international

experience in finance, corporate governance, and regulatory compliance matters. We believe he will be a great addition for us”

continued Mr. Shani.

Mr. Silver currently serves as a corporate advisor and Managing

Director for Alba Capital S.A. and Wicklow Corp., private holding and investment companies. From 2005 to 2015, Mr. Silver was a

Principal at RP Capital UK Ltd., a multi-asset fund focused on liquid and illiquid investments in Eastern Europe, the Middle East and

Africa. Mr. Silver has over 25 years’ experience serving on boards at multiple private and public companies focused primarily

on technology investment. He currently serves on the Board of Directors of Ceva, Inc., a Nasdaq-listed company, where he is Chairman

of the Audit Committee and a member of the Compensation Committee.

Mr. Silver’s appointment brings the size of Ribbon’s

Board to nine members, six of whom are independent. Mr. Silver was appointed as a designee of Swarth Investments Ltd. pursuant to

the Company’s First Amended and Restated Stockholders Agreement.

About

Ribbon

Ribbon Communications

(Nasdaq: RBBN) delivers secure cloud communications and IP

and optical networking solutions to service providers, enterprises and critical infrastructure sectors globally. We engage deeply

with our customers, helping them modernize their networks for improved competitive positioning and business outcomes in today's smart,

always-on and data-hungry world. Our end-to-end portfolio of communications software and IP Optical networking solutions delivers superior

value and innovation by leveraging cloud-native architectures, automation and analytics tools, and leading-edge security.

We maintain a keen focus on our commitments to Environmental, Social, and Governance (ESG) matters, offering an annual Sustainability

Report to our stakeholders. To learn more about Ribbon, please visit rbbn.com

Page 1 of 2

Important Information Regarding Forward-Looking Statements

The information in this release contains forward-looking statements

regarding future events that involve risks and uncertainties. All statements other than statements of historical facts contained in this

release, including those regarding the expected benefits from use of Ribbon Communication’s products, are forward-looking statements.

The actual results of Ribbon Communications may differ materially from those contemplated by the forward-looking statements. For further

information regarding risks and uncertainties associated with Ribbon Communications' business, please refer to the "Risk Factors"

section of Ribbon Communications' most recent annual or quarterly report filed with the SEC. Any forward-looking statements represent

Ribbon Communications' views only as of the date on which such statement is made and should not be relied upon as representing Ribbon

Communications' views as of any subsequent date. While Ribbon Communications may elect to update forward-looking statements at some point,

Ribbon Communications specifically disclaims any obligation to do so.

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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