Item 13. Certain Relationships and Related Transactions, and Director Independence.

Certain Relationships and Related Transactions

There have been no related person transactions or pending related person transactions since January 1, 2023 that require disclosure pursuant to Item 404 of Regulation S-K. Aon has adopted a written Related Person Transaction Policy governing the review and approval of related person transactions. The terms of these procedures provide that the Governance/Nominating Committee will review transactions in which: (i) Aon is a party or participant; and (ii) any director, director nominee, executive officer, or holder of five percent (5%) or more of Aon’s voting securities, an immediate family member of any such person or an entity controlled by any such person or immediate family member, has a direct or indirect material interest. To facilitate the review and approval of related person transactions, Aon’s directors and executive officers complete an annual director and officer questionnaire and disclose all potential related person transactions involving themselves and their immediate family members. Throughout the year, directors and executive officers are required to notify Aon’s General Counsel of any potential related person transactions of which they become aware. Aon’s General Counsel reports these transactions, as well as any other related person transactions of which he is aware, to the Governance/Nominating Committee. The Governance/Nominating Committee considers all relevant facts of any related person transactions to determine whether to approve or ratify the transaction.

Director Independence

Aon’s Corporate Governance Guidelines require that a majority of directors meet the independence requirements of NYSE. The Corporate Governance Guidelines further provide that each of the Audit Committee, Governance/Nominating Committee and Compensation Committee be composed entirely of independent directors.

The Board has affirmatively determined that each nominee for director other than Mr. Case is independent. Mr. Case is considered a management director because of his position as our Chief Executive Officer. In addition, the Board has affirmatively determined that J. Michael Losh, who retired as a director effective as of June 16, 2023, was independent during the time he served on the Board and that Dr. Woo, who will be retiring from the Board effective as of the Annual Meeting, is independent.

In determining that each of the non-management directors is independent, the Board also considered the following relationships that it deemed were immaterial to such director’s independence:

	•		With respect to Mr. Knight, Mr. Campbell, Ms. Karaboutis, and Mr. Spruell, the Board considered that, in the ordinary course of business, Aon has sold services to, or received services from, a company or other entity at which the director is (or during 2023 was) an employee and the amount that we received from or paid to the entity in any of the previous three fiscal years was below the greater of $1 million or two percent (2%) of that entity’s annual revenue; and

	•		With respect to Mr. Knight, Mr. Álvarez, Ms. Francis, Mr. Notebaert, Ms. Santona, and Mr. Spruell, the Board considered that Aon or certain of its affiliates made charitable contributions in 2023 to organizations in which the director or the director’s spouse was an officer, director, or trustee. In each case, the amount that we contributed was below the greater of $1 million or two percent (2%) of that organization’s consolidated gross revenue.

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Item 13. Certain Relationships and Related Transactions, and Director Independence.

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