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UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 FORM 40 - F O REGISTRATION STATEMENT PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 ý OR ANNUAL REPORT PURSUANT TO SECTION 13 ( a ) OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 Commission file number : 001-34152 WESTPORT FUEL SYSTEMS INC . ( Exact Name of Registrant as Specified in its charter ) Alberta ( Province or other jurisdiction of incorporation or organization ) 3537 N / A ( Primary Standard Industrial Classification Code Number ( if applicable ) ) ( I.R.S. Employer Identification Number ( if applicable ) ) 1750 West 75th Avenue , Suite 101 Vancouver , British Columbia , Canada V6P 6G2 ( 604 ) 718-2000 ( Address and telephone number of Registrant's principal executive offices ) CT Corporation System 111 Eighth Avenue New York , NY 10011 ( 212 ) 590-9070 ( Name , address ( including zip code ) and telephone number ( including area code ) of agent for service in the United States ) Copies to : Steven B. Stokdyk , Esq . Lewis W. Kneib , Esq . Latham & Watkins LLP 355 South Grand Avenue , Suite 100 Los Angeles , CA 90071 Securities registered or to be registered pursuant to Section 12 ( b ) of the Act : Title of Each Class : Trading Symbol ( s ) WPRT Name of Each Exchange On Which Registered : NASDAQ Global Select Market Common Shares , no par value Securities registered or to be registered pursuant to Section 12 ( g ) of the Act : N / A Securities for which there is a reporting obligation pursuant to Section 15 ( d ) of the Act : N / A