The bill text is here: https://www.parl.ca/DocumentViewer/en/44-1/bill/C-18/royal-a... The relevant piece from the summary is:

> (d) requires the Canadian Radio-television and Telecommunications Commission (the “Commission”) to maintain a list of digital news intermediaries in respect of which the enactment applies;

CRTC is a government entity so the government reserves the power to decide who is on the list. I couldn't find the list online though.