My Little Pony media, including the comics, novels, and even trading cards, all have to go through Hasbro corporate to be considered suitable for release, which involves properly aligning with the continuity of the main show so it doesn't contradict established canon, or future planned canon. Because of this, other pieces of media have been officially referred to as secondary canon by Hasbro to staff members, such as Jeremy Whitley and Andy Price. This also gives the cartoon authority to directly or indirectly overwrite certain comic stories, thus only non-contradicted stories are included as part of the main canon.