Ticker: CSIQ, Company: Canadian Solar Inc., Type: 20-F, Date: 2012-04-27, XBRL Interactive Financials
Original SEC Filing: Click here

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Webplus: CSIQ/20120427/20-F/1/000.htm SEC Original: a2209108z20-f.htm
Form 20-F (Mark One) o OR ý For the fiscal year ended December 31, 2011. OR o OR o Date of event requiring this shell company report For the transition period from to CANADIAN SOLAR INC. N/A Canada 545 Speedvale Avenue West Michael G. Potter, Chief Financial Officer Title of Each Class Name of Each Exchange on Which Registered Common

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Webplus: CSIQ/20120427/20-F/2_EX-8.1/000.htm SEC Original: a2209108zex-8_1.htm
QuickLinks — Click here to rapidly navigate through this document LIST OF SUBSIDIARIES Name of Significant Subsidiaries Country of Incorporation Ownership Interest CSI Solartronics (Changshu) Co., Ltd. People’s Republic of China 100 % CSI Solar Technologies Inc. People’s Republic of China CSI Solar Manufacture Inc. People’s Republic of China CSI Solar New Energy (Suzhou) Co. Ltd. People’s Republic of China

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Webplus: CSIQ/20120427/20-F/3_EX-12.1/000.htm SEC Original: a2209108zex-12_1.htm
QuickLinks — Click here to rapidly navigate through this document Certification by the Chief Executive Officer I, Shawn (Xiaohua) Qu, certify that: 1. I have reviewed this annual report on Form 20-F of Canadian Solar Inc. (the “Company”); 2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a

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Webplus: CSIQ/20120427/20-F/4_EX-12.2/000.htm SEC Original: a2209108zex-12_2.htm
QuickLinks — Click here to rapidly navigate through this document Certification by the Chief Financial Officer I, Michael G. Potter, certify that: 1. I have reviewed this annual report on Form 20-F of Canadian Solar Inc. (the “Company”); 2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a

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Webplus: CSIQ/20120427/20-F/5_EX-13.1/000.htm SEC Original: a2209108zex-13_1.htm
QuickLinks — Click here to rapidly navigate through this document Certification by the Chief Executive Officer (2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. Shawn (Xiaohua) Qu Chief Executive Officer EX-13.1 5 a2209108zex-13_1.htm EX-13.1

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Webplus: CSIQ/20120427/20-F/6_EX-13.2/000.htm SEC Original: a2209108zex-13_2.htm
QuickLinks — Click here to rapidly navigate through this document Certification by the Chief Financial Officer (2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. Michael G. Potter Chief Financial Officer EX-13.2 6 a2209108zex-13_2.htm EX-13.2

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Webplus: CSIQ/20120427/20-F/7_EX-15.1/000.htm SEC Original: a2209108zex-15_1.htm
QuickLinks — Click here to rapidly navigate through this document CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM We consent to the incorporation by reference in Registration Statement Nos. 333-147042 and 333-178187 on Form S-8 of our reports dated April 27, 2012, relating to the financial statements and financial statement schedule of Canadian Solar Inc. and subsidiaries (the “Company”), and the

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Company Information:

Ticker: CSIQ, Company: Canadian Solar Inc., Type: 20-F, Date: 2012-04-27, XBRL Interactive FinancialsCIK: 0001375877, Location: A6, SIC: 3674, SIC Desc: SEMICONDUCTORS & RELATED DEVICES
Business Phone & Address:
545 SPEEDVALE AVENUE
ONTARIO, A6 N1K 1E6