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Each RSU represents a contingent right to receive one share of the Company's common stock.

The RSUs vested pursuant to the first of three equal annual installments under the reporting person's 2025 Long Term Incentive Plan award, which vests in equal installments on July 9, 2026, July 9, 2027, and July 9, 2028.

The reporting person acquired shares of common stock Octave Specialty Group, Inc. (the "Company") upon the vesting and settlement of a portion of the reporting person's restricted stock unit ("RSU") awards as part of their 2025 Long Term Incentive Plan.

Each RSU represents a contingent right to receive one share of the common stock of the Company's common stock.

The RSUs vested pursuant to the first of three equal annual installments under the reporting person's 2025 Long Term Incentive Plan award, which vests in equal installments on July 9, 2026, July 9, 2027, and July 9, 2028.

The reporting person acquired shares of common stock of Octave Specialty Group, Inc. (the "Company") upon the vesting and settlement of a portion of the reporting person's restricted stock unit ("RSU") awards as part of their 2025 Long Term Incentive Plan.

The reporting person acquired shares of common stock Octave Specialty Group, Inc. (the "Company") upon the vesting and settlement of a portion of the reporting person's restricted stock unit ("RSU") awards as part of their 2025 Long Term Incentive Plan.

Each RSU represents a contingent right to receive one share of the common stock of the Company's common stock.

The RSUs vested pursuant to the first of three equal annual installments under the reporting person's 2025 Long Term Incentive Plan award, which vests in equal installments on July 9, 2026, July 9, 2027, and July 9, 2028.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSUs granted on July 1, 2026 shall vest one year later on July 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company or upon a "change of control" of the Company.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSUs granted on July 1, 2026 shall vest one year later on July 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company or upon a "change of control" of the Company.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSUs granted on July 1, 2026 shall vest one year later on July 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company or upon a "change of control" of the Company.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSUs granted on July 1, 2026 shall vest one year later on July 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company or upon a "change of control" of the Company.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on July 1, 2026 shall vest one year later on July 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on July 1, 2026 shall vest one year later on July 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, or upon a "change of control" of the Company.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on April 1, 2026 shall vest one year later on April 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on April 1, 2026 shall vest one year later on April 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on April 1, 2026 shall vest one year later on April 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on April 1, 2026 shall vest one year later on April 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on April 1, 2026 shall vest one year later on April 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on April 1, 2026 shall vest one year later on April 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

On March 23, 2026 the reporting person received a grant of 99,375 RSUs as part of his 2026 Long Term Incentive Plan award. The RSUs will vest in three equal annual installments commencing March 23, 2027, March 23, 2028, and March 23, 2029.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

On March 23, 2026 the reporting person received a grant of 24,375 RSUs as part of her 2026 Long Term Incentive Plan award. The RSUs will vest in three equal annual installments commencing March 23, 2027, March 23, 2028, and March 23, 2029.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

On March 23, 2026 the reporting person received a grant of 28,246 RSUs as part of his 2026 Long Term Incentive Plan award. The RSUs will vest in three equal annual installments commencing March 23, 2027, March 23, 2028, and March 23, 2029.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

On March 23, 2026 the reporting person received a grant of 26,250 RSUs as part of his 2026 Long Term Incentive Plan award. The RSUs will vest in three equal annual installments commencing March 23, 2027, March 23, 2028, and March 23, 2029.

Each RSU represents a contingent right to receive one share of the Company's common stock.

On March 23, 2026 the reporting person received a grant of 8,067 restricted stock units ("RSUs") as part of her 2026 Long Term Incentive Plan award. The RSUs will vest in three equal annual installments commencing March 23, 2027, March 23, 2028, and March 23, 2029.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

Each RSU represents a contingent right to receive one share of the Company's common stock.

Represents the aggregate amount of restricted stock units ("RSUs") that were converted into shares of common stock of Octave Specialty Group, Inc. (the "Company") upon settlement of a portion of the reporting person's 2025 Long Term Incentive Plan award.

Represents the aggregate amount of restricted stock units ("RSUs") that were converted into shares of common stock of Octave Specialty Group, Inc. (the "Company") upon settlement of a portion of the reporting person's 2025 Long Term Incentive Plan award.

Each RSU represents a contingent right to receive one share of the Company's common stock.

Represents the aggregate amount of RSUs that vested.

Each RSU represents a contingent right to receive one share of the common stock of the Company.

Represents the aggregate amount of RSUs that vested.

Each RSU represents a contingent right to receive one share of the Company's common stock.

Represents the aggregate amount of RSUs that vested.

Each deferred share unit ("DSU") represents a contingent right to receive one share of common stock of the Company.

Represents the aggregate amount of RSUs that were converted into an equivalent number of DSUs pursuant to the Company's Executive Stock Deferral Plan, which was designed to enable participants to elect to defer the settlement and income taxation of RSU and Performance Stock Unit awards in accordance with Section 409A of the Internal Revenue Code of 1986, as amended.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

The reporting person acquired shares of common stock of Octave Specialty Group, Inc. (the "Company") upon the vesting and settlement of a portion of the reporting person's 2023 and 2024 restrictive stock unit ("RSU") awards.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

The reporting person acquired shares of common stock of Octave Specialty Group, Inc. (the "Company") upon the vesting and settlement of a portion of the reporting person's 2023 and 2024 restrictive stock unit ("RSU") awards.

Each deferred share unit ("DSU") represents a contingent right to receive one share of common stock of the Company.

Represents the aggregate amount of RSUs that were converted into an equivalent number of DSUs pursuant to the Company's Executive Stock Deferral Plan, which was designed to enable participants to elect to defer the settlement and income taxation of RSU and Performance Stock Unit awards in accordance with Section 409A of the Internal Revenue Code of 1986, as amended.

Represents the amount of RSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.

The reporting person acquired shares of common stock of Octave Specialty Group, Inc. (the "Company") upon the vesting and settlement of a portion of the reporting person's 2023 and 2024 restrictive stock unit ("RSU") awards.

Each deferred share unit ("DSU") represents a contingent right to receive one share of common stock of the Company.

Represents the aggregate amount of RSUs that were converted into an equivalent number of DSUs pursuant to the Company's Executive Stock Deferral Plan, which was designed to enable participants to elect to defer the settlement and income taxation of RSU and Performance Stock Unit awards in accordance with Section 409A of the Internal Revenue Code of 1986, as amended.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on January 1, 2026 shall vest one year later on January 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on January 1, 2026 shall vest one year later on January 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on January 1, 2026 shall vest one year later on January 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on January 1, 2026 shall vest one year later on January 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on January 1, 2026 shall vest one year later on January 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Each restricted stock unit ("RSU") represents a contingent right to receive one share of the common stock of Octave Specialty Group, Inc. (the "Company").

RSU's granted on January 1, 2026 shall vest one year later on January 1, 2027. RSUs that have become vested shall settle and convert into shares of common stock upon the earlier of the vesting date or the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company, unless otherwise deferred upon the election of the Reporting person.

Shares were purchased as gift to the reporting persons son.