MAPL defines Canadian content for Canadian radio stations.
M = "music" composed by a Canadian
A = "artist" is Canadian
P = "production" was recorded in Canada
L - "lyrics" were written by a Canadian
To qualify as Canadian content, a song has to meet any two of the four criteria.
Thus, if I record a Gordon Lightfoot song, it qualifies because it'll be ML.
However, if Gordon records one of my songs at a studio in Boston, it will not be Canadian content because it's just A. But if Gordon recorded my song at a studio in Toronto, it would be Canadian content because it would be AP.
An exception, for anything recorded before 1970, a song only needs to meet one of the four criteria to qualify.