ACGL · Arch Capital Group Ltd.

Includes 1,820,981 shares held by the revocable trust that were previously reported on separate lines.

The common shares are held by a revocable trust. The reporting person and his spouse are the trustees and the beneficiaries.

Each Depositary Share Represents 1/1,000th interest in a Series F Non-Cumulative Preferred Share.

The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $19.57 to $19.80. Upon request, the full information regarding the number of shares sold at each separate price within the range will be provided to the issuer, any security holder of the issuer or the staff of the Securities Exchange Commission.

Each Depositary Share Represents 1/1,000th interest in a Series G Non-Cumulative Preferred Share.

The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $17.14 to $17.17. Upon request, the full information regarding the number of shares sold at each separate price within the range will be provided to the issuer, any security holder of the issuer or the staff of the Securities Exchange Commission.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Represents shares granted as part of the director-elected retainer for serving as the Chair of the Issuer. Upon grant, the reporting person contributed such shares to a revocable trust. The reporting person and his spouse are the trustees and the beneficiaries.

Amount includes 1,564 common shares that were previously reported as directly owned by the reporting person and were contributed to the trust on May 6, 2026.

The common shares are held by a revocable trust. The reporting person and his spouse are the trustees and the beneficiaries.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Represents shares granted as part of the director-elected retainer for serving as a director of the Issuer. Upon grant, the reporting person contributed such shares to a revocable trust. The reporting person and his spouse are the trustees and the beneficiaries.

Amount includes 1,564 common shares that were previously reported as directly owned by the reporting person and were contributed to the trust on May 6, 2026.

The common shares are held by a revocable trust. The reporting person and his spouse are the trustees and the beneficiaries.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Represents shares granted as part of the director-elected annual retainer for serving as a director of the Issuer.

Subject to the terms of the restricted share agreement, represents restricted shares that will become vested on the date that is the earlier of 1) one year following the grant date or 2) Arch Capital Group Ltd.'s next Annual General Meeting of Shareholders.

Represents shares granted as part of the director-elected annual retainer for serving as a director of the Issuer.

Represents shares granted as part of the director-elected annual retainer for serving as a director of the Issuer.

Represents shares granted as part of the director-elected annual retainer for serving as a director of the Issuer.

The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $94.02 to $94.11. Upon request, the full information regarding the number of shares sold at each separate price within the range will be provided to the issuer, any security holder of the issuer or the staff of the Securities Exchange Commission.

Each Depositary Share Represents 1/1,000th interest in a Series G Non-Cumulative Preferred Share.

The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $17.1149 to $17.1150. Upon request, the full information regarding the number of shares sold at each separate price within the range will be provided to the issuer, any security holder of the issuer or the staff of the Securities Exchange Commission.

This stock option is exercisable in three equal annual installments commencing May 13, 2017, and the next two installments on May 13, 2018 and May 13, 2019, subject to the applicable award agreement.

This stock option is exercisable in three equal annual installments commencing May 13, 2017, and the next two installments on May 13, 2018 and May 13, 2019, subject to the applicable award agreement.

The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $96.00 to $96.54. Upon request, the full information regarding the number of shares sold at each separate price within the range will be provided to the issuer, any security holder of the issuer or the staff of the Securities Exchange Commission.

The price reported is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $96.35 to $96.42. Upon request, the full information regarding the number of shares sold at each separate price within the range will be provided to the issuer, any security holder of the issuer or the staff of the Securities Exchange Commission.

The reporting person contributed the Common Shares to a wholly-owned LLC (of which he is the manager), immediately following which he transferred, for no consideration, all of the outstanding ownership interests of the LLC to two irrevocable trusts (50% each) established for the primary benefit of his descendants and of which his brother is the trustee. The reporting person disclaims beneficial ownership of the shares held directly by the LLC for purposes of Section 16 of the Securities Exchange Act of 1934, except to the extent of his pecuniary interest therein.

The reporting person contributed the Common Shares to a wholly-owned LLC (of which he is the manager), immediately following which he transferred, for no consideration, all of the outstanding ownership interests of the LLC to two irrevocable trusts (50% each) established for the primary benefit of his descendants and of which his brother is the trustee. The reporting person disclaims beneficial ownership of the shares held directly by the LLC for purposes of Section 16 of the Securities Exchange Act of 1934, except to the extent of his pecuniary interest therein.

This stock option is exercisable in three equal annual installments commencing March 3, 2027, and the next two installments on March 3, 2028 and March 3, 2029, subject to the applicable award agreement.

This stock option is exercisable in three equal annual installments commencing March 3, 2027, and the next two installments on March 3, 2028 and March 3, 2029, subject to the applicable award agreement.

This stock option is exercisable in three equal annual installments commencing March 3, 2027, and the next two installments on March 3, 2028 and March 3, 2029, subject to the applicable award agreement.

This stock option is exercisable in three equal annual installments commencing March 3, 2027, and the next two installments on March 3, 2028 and March 3, 2029, subject to the applicable award agreement.

This stock option is exercisable in three equal annual installments commencing March 3, 2027, and the next two installments on March 3, 2028 and March 3, 2029, subject to the applicable award agreement.

This stock option is exercisable in three equal annual installments commencing March 3, 2027, and the next two installments on March 3, 2028 and March 3, 2029, subject to the applicable award agreement.

Amount includes 248 Common Shares acquired on May 30, 2025 under the Arch Capital Group Ltd. Employee Share Purchase Plan.

Amount reflects an adjustment for 902 Common Shares purchased under the Arch Capital Group Ltd. Employee Share Purchase Plan that were inadvertently double counted in the amount of securities beneficially owned on the reporting person's Form 4 filed on March 3, 2025, and subsequent Forms 4.

Amount includes 248 Common Shares acquired on May 30, 2025 under the Arch Capital Group Ltd. Employee Share Purchase Plan.