Grupo Argos S.A. - 10 Feb 2025 Form 4 Insider Report for Summit Materials, Inc.

Footnote F1

This Form 4 is filed jointly by (i) Grupo Argos S.A., a sociedad anonima incorporated in the Republic of Colombia ("Grupo Argos"), (ii) Argos SEM, LLC, a Delaware limited liability company ("Argos SEM"), (iii) Valle Cement Investments, Inc., a sociedad anonima incorporated in the Republic of Panama ) ("Valle Cement") and (iv) Cementos Argos S.A., a sociedad anonima incorporated in the Republic of Colombia ("Cementos Argos" and collectively with Grupo Argos, Argos SEM and Valle Cement, the "Reporting Persons"). Grupo Argos is the controlling shareholder of Cementos Argos and has the power to control and direct Cementos Argos. Cementos Argos is the sole shareholder of Argos SEM and Valle Cement. By reason of these relationships and the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, each of the Reporting Persons may be deemed to beneficially own the shares of Common Stock of the Issuer directly owned by Valle Cement, Argos SEM and Cementos Argos.

Footnote F2

(Continued from footnote 1) Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of its pecuniary interest therein.

Footnote F3

Reflects the disposition of shares of common stock, par value $0.01 per share ("Common Stock"), of Summit Materials Inc. ("Issuer"), in connection with the consummation of the transactions contemplated by the Agreement and Plan of Merger, dated as of November 24, 2024 (the "Merger Agreement"), by and among the Issuer, Quikrete Holdings, Inc. ("Parent") and Soar Subsidiary, Inc. ("Merger Sub"), a wholly owned subsidiary of Parent, pursuant to which, at the effective time of the Merger (the "Effective Time"), Merger Sub merged with and into the Issuer, with the Issuer surviving as a subsidiary of Parent (the "Merger"). Pursuant to the Merger, on the Effective Time, each issued and outstanding share of the Issuer's (i) Class A Common Stock and (ii) Class B common stock, par value $0.01 per share (together with the Class A Common Stock described in the foregoing clause (i), "Company Common Shares"

Footnote F4

(Continued from footnote 3) and each, a "Company Common Share") (other than any Company Common Shares that are held by the Issuer as treasury stock or held by Purchaser, Merger Sub or any other subsidiary of Purchaser or the Issuer or any Company Common Shares as to which appraisal rights have been properly exercised in accordance with Delaware law), was automatically canceled and retired and converted into the right to receive $52.50 per share in cash, without interest and subject to deduction for any required withholding (the "Merger Consideration"). Furthermore, on the Effective Time of the Merger, all shares of preferred stock of the Issuer, par value $0.01 per share, outstanding immediately prior to the Effective Time, ceased to exist as they were automatically canceled and retired for no consideration.

Footnote F5

Represents securities of the Issuer, directly owned by Argos SEM, which is a wholly-owned subsidiary of Cementos Argos, which is a majority-owned subsidiary of Grupo Argos. Grupo Argos, as the controlling shareholder of Cementos Argos, which in turn is the sole shareholder of Argos SEM, has the power to vote and to dispose of the Company Common Shares directly owned by Argos SEM. As a result of this relationship, Grupo Argos may be deemed to be an indirect beneficial owner of the securities that are beneficially owned by Argos SEM. By reason of the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, each of the Reporting Persons may be deemed to beneficially own the Company Common Shares directly owned by Argos SEM.

Footnote F6

Represents securities of the Issuer, directly owned by Valle Cement, which is a wholly-owned subsidiary of Cementos Argos, which is a majority-owned subsidiary of Grupo Argos. Grupo Argos, as the controlling shareholder of Cementos Argos, which in turn is the sole shareholder of Valle Cement, has the power to vote and to dispose of the Company Common Shares directly owned by Valle Cement. As a result of this relationship, Grupo Argos may be deemed to be an indirect beneficial owner of the securities that are beneficially owned by Valle Cement. By reason of the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, each of the Reporting Persons may be deemed to beneficially own the Company Common Shares directly owned by Valle Cement.

Footnote F7

Represents securities of the Issuer, directly owned by Cementos Argos, which is a majority-owned subsidiary of Grupo Argos. Grupo Argos, as the controlling shareholder of Cementos Argos, has the power to vote and to dispose of the share of Series A Non-Convertible Preferred Stock of the Issuer directly owned by Cementos Argos. As a result of this relationship, Grupo Argos may be deemed to be an indirect beneficial owner of the securities that are beneficially owned by Cementos Argos. By reason of the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, each of the Reporting Persons may be deemed to beneficially own the shares of Common Stock of the Issuer directly owned by Cementos Argos.