Colliers International Group Inc.

Issuer

Colliers International Group Inc.

Security title

Subordinate Voting Shares

Principal address

Comment

This Amendment No. 1 to Schedule 13D ("Amendment No. 1") relates to the Subordinate Voting Shares (the "Shares"), of Colliers International Group Inc., a Canadian corporation (the "Issuer"), and amends the initial statement on Schedule 13D filed with the Securities and Exchange Commission (the "SEC") on April 6, 2026 (the "Schedule 13D"). All capitalized terms contained herein but not otherwise defined shall have the meanings ascribed to such terms in the Schedule 13D. The Schedule 13D is hereby amended as set forth in this Amendment No. 1. Except as set forth herein, the Schedule 13D is unmodified.

Source of funds

Item 3 of the Schedule 13D is hereby amended and supplemented to reflect the following: The 3,235,000 Shares beneficially owned by Spruce Partnership were purchased with working capital (which may, at any given time, include margin loans made by brokerage firms in the ordinary course of business). Of such 3,235,000 Shares, 3,069,800 Shares were purchased in open market transactions for an aggregate purchase price of approximately $238,198,799, including brokerage commissions and, on February 28, 2024, 165,200 Shares were purchased in an underwritten public offering at a price of $121.00 per Share for an aggregate purchase price of $19,989,200, including brokerage commissions. Of the 47,012 Shares owned directly by Benjamin Stein, 17,696 Shares were purchased with personal funds through the exercise of stock options that were received in connection with Mr. Stein's tenure as a member of the board of directors of the Issuer for an aggregate purchase price of approximately $1,184,863, including brokerage commissions, 5,129 Shares were received by Mr. Stein upon the dissolution of the Ben Stein 2011 Trust, pursuant to a distribution of all trust assets to Mr. Stein by the trustee for no cash or other consideration, and 24,187 Shares are issuable upon the exercise of stock options that were received in connection with Mr. Stein's tenure as a member of the board of directors of the Issuer.

Number of shares

Item 5(b) of the Schedule 13D is hereby amended and supplemented to reflect the following: See rows (7) through (10) of the cover pages to this Amendment No. 1 for the number of Shares as to which each Reporting Person has the sole or shared power to vote or direct the vote and the sole or shared power to dispose or to direct the disposition.

Transactions

Item 5(c) of the Schedule 13D is hereby amended and supplemented to reflect the following: Schedule I annexed hereto and incorporated herein by reference lists all transactions in the Shares that were effected during the past sixty days by the Reporting Persons, inclusive of any transactions effected through 4:00 p.m., New York City time, on September 28, 2026.

Other persons with an interest

Item 5(d) of the Schedule 13D is hereby amended and supplemented to reflect the following: No person other than the Reporting Persons is known to have the right to receive, or the power to direct the receipt of dividends from, or proceeds from the sale of, the Shares beneficially owned by the Reporting Persons.

Date ownership ceased to exceed 5%

Item 5(e) of the Schedule 13D is hereby amended and supplemented to reflect the following: Not applicable.

Percentage of class

Item 5(a) of the Schedule 13D is hereby amended and supplemented to reflect the following: The aggregate percentage of Shares beneficially owned by each Reporting Person is based upon 49,778,127 Shares outstanding as of August 5, 2026, which is the total number of Shares outstanding as reported in the Issuer's Report of Foreign Private Issuer on Form 6-K filed with the SEC on August 5, 2026. As of the date hereof, Spruce Investment, as the investment adviser of Spruce AI and Spruce QP, which are each members of Spruce Partnership, may be deemed the beneficial owner of the 3,235,000 Shares owned by Spruce Partnership, representing approximately 6.5% of the outstanding Shares. As of the date hereof, Spruce Capital, as the general partner of Spruce AI and Spruce QP, which are each members of Spruce Partnership, may be deemed the beneficial owner of the 3,235,000 Shares owned by Spruce Partnership, representing approximately 6.5% of the outstanding Shares. As of the date hereof, 3,235,000 Shares are held in the account of Spruce Partnership, representing approximately 6.5% of the outstanding Shares. As of the date hereof, Mr. Sternberg, as the manager of each of Spruce Investment and Spruce Capital, may be deemed the beneficial owner of the 3,235,000 Shares owned by Spruce Partnership, representing approximately 6.5% of the outstanding Shares. As of the date hereof, Mr. Stein directly beneficially owns 47,012 Shares, including 24,187 Shares issuable upon exercise of stock options held by Mr. Stein that are currently exercisable or will become exercisable within 60 days. Mr. Stein, as the manager of each of Spruce Investment and Spruce Capital, may be deemed the beneficial owner of the 3,235,000 Shares owned by Spruce Partnership, representing (together with the Shares directly beneficially owned by Mr. Stein) approximately 6.6% of the outstanding Shares. In addition, Mr. Stein holds stock options to acquire an additional 9,563 Shares that are not exercisable within 60 days and are not counted as beneficially owned securities for purposes of Rule 13d-3 under the Act and are excluded from the amounts reported above. Mr. Stein also holds 3,960 deferred share units ("DSUs") granted as director compensation. These DSUs are fully vested; however, they are payable in cash following cessation of his service on the Issuer's board of directors and do not entitle the holder to acquire Shares within 60 days. Accordingly, the DSUs are not counted as beneficially owned securities for purposes of Rule 13d-3 under the Act and are excluded from the amounts reported above. The Reporting Persons may be deemed to constitute a "person" or "group" within the meaning of Section 13(d)(3) of the Act. Each Reporting Person disclaims beneficial ownership of the securities reported herein except to the extent of its or his pecuniary interest therein, and the filing of this statement shall not be construed as an admission of such beneficial ownership or that the Reporting Persons constitute a person or group.

Filed exhibits

Item 7 of the Schedule 13D is hereby amended and supplemented to reflect the following: Schedule I - Transactions in Securities of the Issuer During the Past Sixty Days