There are varying definitions of a mass shooting. Listed roughly from most broad to most restrictive: :
Stanford MSA Data Project: 3+ shot in one incident, at one location, at roughly the same time, excluding organized crime, as well as gang-related and drug-related shootings. : Mass Shooting Tracker: 4+ shot in one incident, at one location, at roughly the same time. :
The Washington Post: 4+ shot and killed in one incident, excluding the perpetrator(s), at a public place, excluding gang-related killings. Only shootings that have Wikipedia articles of their own are included in this list. Detailed lists of shootings can be found per-year at their respective pages. == List ==