 Some people, however, consider this tantamount to censorship.The CRTC's simultaneous substitution rules require that when a Canadian network licences a television show from a US network and shows it in the same time slot, upon request by the Canadian broadcaster, Canadian broadcast distributors must replace the show on the US channel with the broadcast of the Canadian channel, along with any overlays and commercials.As "Grey's Anatomy" is on ABC, but is carried in Canada on CTV at the same time, for instance, the cable, satellite, or other broadcast distributor must send the CTV feed over the signal of the carried ABC affiliate, even where the ABC version is somehow different, particularly commercials.