Exhibit 21 IMAX CORPORATION Significant and other major subsidiary companies of the Registrant at December 31, 1999 were: Name of Subsidiary Jurisdiction of Percentage held - ------------------ -------------- --------------- Organization by Registrant ------------ ------------- Imax Ltd. Ontario 100% David Keighley Productions 70MM Inc. Delaware 100% Sonics Associates, Inc. Alabama 100% Ridefilm Corporation Delaware 100% 1236627 Ontario Inc. Ontario 100% Imax Japan Inc. Japan 100% Imax Entertainment Pte. Ltd. Singapore 100% Imax (Netherlands) B.V. Netherlands 100% Imax U.S.A. Inc. Delaware 100% Nyack Theater L.L.C. Delaware 100% Arizona Big Frame Theatres, L.L.C. Delaware 50% Starboard Theaters Ltd. Canada 100% Forum Ride Associates Nevada 50% Miami Theatre, L.L.C. Delaware 100% Digital Projection International Limited U.K. 100% Digital Projection Inc. Georgia 100% Themax Inc. (Brossard) Quebec 33% Sacramento Theatre L.L.C. Delaware 100% Panada Productions Inc. Delaware 100% Wire Frame Films Ltd. Ontario 100%