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·完整,在 背面签名并注明日期。 ·将此表格放入提供的 信封中返回。 ·您可以通过访问 www.investorcentre.com以电子方式注册接收未来的 安全持有人通信 。 ·访问以下网站: www.investorvote.com ·智能手机? 扫描二维码 立即投票。 ·您可以通过访问URL以虚拟方式参加会议 此委托书背面提供。 01 VSEC 折叠表 折叠表 将于4月27日举行的年度会议,2023年。 一周7天、每天24小时使用电话或互联网投票。 如果您通过电话或互联网投票,请勿邮寄此表。 只有邮寄或互联网投票才是持有人指定代理人以外的人的唯一方法。 代理人表格背面指定的管理层被提名人除外。您可以选择上述两种投票方式中的一种来投票此委托书,而不是邮寄此委托书。 要通过电话或互联网投票,您需要提供下面列出的控制编号。 . 控制编号 1.您有权指定其他人、公司或您选择的其他法人实体(“被指定人”)出席年会或其任何续会或延期会议并代表您行事。如果您希望委任的人、公司或其他法人实体的姓名不在此列,请在所提供的空白处填写您所选择的被任命人的姓名(见背面)。此外,您必须访问 https://www.computershare.com/Celestica并向ComputerShare提供所选被任命人的所需信息,以便ComputerShare可以通过电子邮件向 被任命者提供邀请码。此邀请代码将允许您的被任命人登录并在年会上投票。如果没有邀请代码 您指定的人将只能以嘉宾身份登录年会,并且不能投票。 2.如果证券是以多个所有者(例如,共同所有人、受托人、遗嘱执行人等)的名义注册的,则所有注册的人都应在此委托书上签名。 如果您代表公司、其他法人实体或其他个人投票,您必须在此委托书上签名,并注明签名能力,并且您可能需要提供 证明您有权签署此委托书的文件。 3.此委托书的签名方式应与委托书上的姓名(S)(S)完全相同。 4.如果此委托书没有注明日期,它将被视为具有管理层邮寄给您的日期。 5.此委托书所代表的证券,在正确执行后,将根据您的指示投赞成票、反对票或弃权票,但是,如果您没有就任何事项指示您的投票,并且您没有指定指定的人作为您的委托持有人,则此委托书将被投票:用于选举管理层提名的Celestica Inc.董事进入董事会;任命毕马威有限责任公司为Celestica Inc.的审计师;授权Celestica Inc.董事会确定审计师的薪酬;6.本委托书授权酌情处理股东周年大会或其任何延会或延期的会议通告或其他事项。 7.本委托书应与股东周年大会通告及管理层资料通告一并阅读。 递交的委托书必须于上午9:30前收到。美国东部夏令时2023年4月25日,如果年会延期或延期,则在年会休会或延期前至少48小时,不包括星期六、星期日和法定节假日。 委托书须知 ·通过按键 电话拨打下列号码。 多伦多大学大道100号8楼,安大略省M5J 2Y1 www.ComputerShar.com 投票使用 电话 投票使用 互联网 虚拟出席 年会通过邮寄投票接收文件 电子 Sample先生 Samples街123 Samples Street SAMPLETOWN SS X9X 9X9安全等级 下属投票股份 C1234567890 XXX 持有者帐号 CPUQC01.E.INT/000001/i1234 123456789012345 1-866-732-Vote(8683)

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348595 Fold Fold . AR1 If you are not mailing back your form of proxy, you may register online to receive the above financial report(s) by mail at www.computershare.com/mailinglist. Interim Financial Statements – Mark this box if you would like to receive Interim Financial Statements and accompanying Management’s Discussion and Analysis by mail. Annual Financial Statements – Mark this box if you would like to receive the Annual Financial Statements and accompanying Management’s Discussion and Analysis by mail. 01VSFB Authorized Signature(s) – This section must be completed for your instructions to be executed. I/We authorize you to act in accordance with my/our instructions set out above. I/We hereby revoke any form of proxy previously given with respect to the Annual Meeting. If no voting instructions are indicated above, this form of proxy will be voted as recommended by Management. DD . / MM / YY Signature(s) Date Appointment of Proxyholder Instead of either of the foregoing, print the name of the person you are appointing as an Appointee if this person is someone other than the Management Nominees listed herein. I/We, being holder(s) of Subordinate Voting Shares of Celestica Inc. hereby appoint: Michael M. Wilson or, failing him, Robert A. Mionis, or their designees (Management Nominees) OR as my/our proxyholder with full power of substitution and to attend, act and to vote in accordance with the following direction (or if no directions have been given, as the proxyholder sees fit) and to vote at the discretion of the proxyholder with respect to amendments or variations to matters identified in the Notice of Meeting or other matters that may properly come before the Annual Meeting of Shareholders of Celestica Inc. to be held virtually at https://meetnow.global/MR6KD4X on April 27, 2023 at 9:30 a.m., EDT and at any adjournments or postponements thereof. VOTING RECOMMENDATIONS OF MANAGEMENT ARE INDICATED BY HIGHLIGHTED TEXT OVER THE BOXES. Note: If completing the appointment box above YOU MUST go to http://www.computershare.com/Celestica and provide Computershare with the name and email address of the person you are appointing. Computershare will use this information ONLY to provide the Appointee with an Invitation Code to gain entry to and vote at the online meeting. This form of proxy is solicited by and on behalf of Management. 1. Election of Directors 4. Advisory resolution on Celestica Inc.’s approach to executive compensation For Against For Withhold For Withhold For Withhold 2. Appointment of auditor Appointment of KPMG LLP as auditor of Celestica Inc. For Withhold 3. Authority to fix the remuneration of the auditor Authorization of the Board of Directors of Celestica Inc. to fix the remuneration of the auditor. For Withhold 01. Robert A. Cascella 04. Daniel P. DiMaggio 07. Robert A. Mionis 02. Deepak Chopra 05. Jill Kale 08. Luis A. Müller 09. Tawfiq Popatia 03. Françoise Colpron 06. Laurette T. Koellner 10. Michael M. Wilson MR SAM SAMPLE 123 C1234567890 XXX CLSQ 999999999999