Dzogchen

Dzogchen (rdzogs pa chen po, Skt. mahasandhi. Also known as Great Perfection and Ati Yoga. The highest teachings of the Nyingma School of the Early Translations. In this world the most well known human lineage masters are: Garab Dorje, Manjushrimitra, Shri Singha, Jnanasutra, Vimalamitra, Padmasambhava and Vairotsana.
Dzogchen has two chief aspects: the lineage of scriptures and the lineage of teachings (dpe brgyud dang bka' brgyud). The scriptures are contained in the tantras of the Three Sections of Dzogchen: Mind Section, Space Section and Instruction Section. The first two were brought to Tibet chiefly by Vairotsana while the Instruction Section was mainly transmitted by Vimalamitra and Padmasambhava. In addition, numerous Dzogchen termas were concealed by these masters and revealed through the following centuries. The lineage of teachings is embodied in the oral instructions one receives personally from a qualified master and holder of the Dzogchen lineage.
The Tibetan historian Guru Tashi Tobgyal elaborates in his Ocean of Wondrous Sayings about Padmasambhava's specific lineage of Dzogchen in the following way: "The great master is of the same nature as the infinite number of buddhas of the three kayas and does therefore not depend upon the concept of linear transmission. He is indivisible from the buddhas and the pure realms of the three kayas. However, in accordance with how other people perceive, Padmasambhava is not only the master of the numberless tantras of Vajrayana but possesses a unique short lineage of mastery over the profound topics of Nyingtig, the Luminous Great Perfection of the definitive meaning, entrusted to him by the three masters Garab Dorje, Manjushrimitra and Shri Singha. In particular, Padmasambhava acted upon a prophesy from Vajra Varahi and then received detailed teachings from Shri Singha.