Mingyur Rinpoche holds many lineages....
His family Lineage is the Chokling Tersar, through his father, the great Dzogchen master, Tulku Urgyen.
He is primarily a Karma Kagyu Tulku , associated with the Palpung tradition of Tai Situpa, and has completed extensive retreats in this Lineage.... but he is also considered a Tulku of a great Nyingma Lama called Kangyur Rinpoche, and teaches at his centres.
MR also directly holds a important and rare Dzogchen Lineage called the 'Mengak Nyengyu Chenmo' closely associated with the Longchen Nyingthig, through his Guru, Nyoshul Khenpo, which is the profound hearing lineage transmitted from a master to student secretly and one on one.
Finally MR holds his own Terma Lineage from the first Mingyur Dorje in the 17th century.... Which includes, amongst others, the well known Karma Pakshi Guru Yoga and a cycle on Dorje Drollo, both widely practised by Karma Kagyus today.
He is an amazing teacher and the fact he is in mountain retreat in this day and age only proves that.