According to the "Dipavamsa" of the Pāli tradition, they started immediately after the Second Council, the Puggalavada tradition places it in 137 AN, the Sarvastivada tradition of Vasumitra says it was in the time of Ashoka and the Mahasanghika tradition places it much later, nearly 100 BCE.
Pripadajo mu sveta besedila, kot so Vinaja pitaka in štiri glavne nikaje ali agame.