The recognition of the Seventeenth Karmapa, the head of the Karma Kagyu sect of Tibetan Buddhism, has been the subject of controversy. Since the death of the sixteenth Karmapa, Rangjung Rigpe Dorje, in 1981, two candidates have been put forward: Ogyen Trinley Dorje (also spelled Urgyen Trinley Dorje, born 1985) and Trinley Thaye Dorje (born 1983). Both have already been enthroned as 17th Karmapa, and both independently have been performing ceremonial duties in the role of a Karmapa. They have not met, though both have expressed a willingness and desire to meet. As one academic expert in the field testified in court, while the recognition of Ogyen Trinley ""appears to have been accepted by a majority of Karma Kagyu monasteries and lamas, there remains a substantial minority of monasteries and lamas who have not accepted Ogyen Trinley as Karmapa. In particular, these include the Shamar Rinpoche, who historically has been the person most directly involved in the process of recognition."" It is difficult to produce an objective description of the events because the most important developments are known only from conflicting accounts by those involved.The Karmapa lineage is the most ancient tulku lineage in Tibetan Buddhism, predating the Dalai Lama lineage by more than two centuries. The lineage is an important one as the Karmapa is traditionally the head of the Karma Kagyu school.