# EDGAR Filing Document

**Accession Number:** 0001690129
**File Stem:** 0001708055-25-000039
**Filing Date:** 2025-11
**Character Count:** 8048
**Document Hash:** dabfc7fd5fa394252fe87b2a9fe72c47
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001708055-25-000039.hdr.sgml**: 20251104

**ACCESSION NUMBER**: 0001708055-25-000039

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251031

**FILED AS OF DATE**: 20251104

**DATE AS OF CHANGE**: 20251104

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** McCaffery Stephen J.
- **CENTRAL INDEX KEY:** 0001690129

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38267
- **FILM NUMBER:** 251449653

**MAIL ADDRESS:**
- **STREET 1:** VICTORIA ROAD
- **STREET 2:** WEST YORKSHIRE
- **CITY:** SALTAIRE
- **STATE:** X0
- **ZIP:** BD183LF
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Ribbon Communications Inc.
- **CENTRAL INDEX KEY:** 0001708055
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-COMPUTER INTEGRATED SYSTEMS DESIGN [7373]
- **ORGANIZATION NAME:** 06 Technology
- **EIN:** 821669692
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 6500 CHASE OAKS BOULEVARD
- **CITY:** PLANO
- **STATE:** TX
- **ZIP:** 75023
- **BUSINESS PHONE:** 877-412-8867

**MAIL ADDRESS:**
- **STREET 1:** 6500 CHASE OAKS BOULEVARD
- **CITY:** PLANO
- **STATE:** TX
- **ZIP:** 75023

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Sonus Networks, Inc.
- **DATE OF NAME CHANGE:** 20171027

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Solstice Sapphire Investments, Inc.
- **DATE OF NAME CHANGE:** 20170531

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>McCaffery Stephen J.<br><sub>(Last) (First) (Middle)</sub><br>C/O RIBBON COMMUNICATIONS<br>6500 CHASE OAKS BLVD.<br><sub>(Street)</sub><br>PLANO, TX 75023<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2025-10-31 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_EVP, Global Sales_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Ribbon Communications Inc. [ RBBN ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |  |  |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Restricted Stock Units (RSUs) | <sup>(1)</sup> | 2025-10-31 |  | A |  | 432027 |  | <sup>(2)</sup> | <sup>(2)</sup> | Common Stock | 432027 | $0 | 432027 | D |  |
| RSUs | <sup>(1)</sup> | 2025-10-31 |  | A |  | 108006 |  | <sup>(3)</sup> | <sup>(3)</sup> | Common Stock | 108006 | $0 | 108006 | D |  |
| Performance-Based RSUs (PSUs) | <sup>(1)</sup> | 2025-10-31 |  | A |  | 64804 |  | <sup>(4)</sup> | <sup>(4)</sup> | Common Stock | 64804 | $0 | 64804 | D |  |
| PSUs | <sup>(1)</sup> | 2025-10-31 |  | A |  | 43202 |  | <sup>(5)</sup> | <sup>(5)</sup> | Common Stock | 43202 | $0 | 43202 | D |  |

---

### Footnotes:

(1) Each RSU and PSU converts into common stock on a one-for-one basis.

(2) The RSUs were awarded on October 31, 2025 and vest as to 108,007 shares on the first anniversary of the date of grant, with the remaining RSUs vesting in six equal semi-annual installments thereafter through October 31, 2029.

(3) The RSUs were awarded on October 31, 2025 and vest as to 36,002 shares on the first anniversary of the date of grant, with the remaining RSUs vesting in four equal semi-annual installments thereafter through October 31, 2028.

(4) The PSUs were awarded on October 31, 2025. The number of PSUs earned and issuable upon vesting will be determined based on goals (set by the Compensation Committee on an annual basis) for each of the three fiscal years ending December 31, 2025, 2026 and 2027. The aggregate number of shares issued may range from zero shares to 150% of the target number of shares reported in column 3 of Table II. The number of PSUs reported in column 3 of Table II reflects achievement at the target level of performance. The PSUs will vest on May 15, 2028.

(5) The PSUs were awarded on October 31, 2025. The number of PSUs earned and issuable upon vesting will be determined based on the Issuer's total shareholder return (TSR) compared to pre-established relative TSR goals, based on the TSR of a peer index of companies (set by the Compensation Committee at the time of grant) over the period beginning on the grant date and ending December 31, 2028. The aggregate number of shares issued may range from zero shares to 200% of the target number of shares reported in column 3 of Table II. The number of PSUs reported in column 3 of Table II reflects achievement at the target level of performance.   The PSUs will vest on May 15, 2029.

**Signature:** Stephen J. McCaffery  
**Date:** 2025-11-04

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**