Zen is based on face-to-face transmission, ever since Shakyamuni Buddha held up a flower to the assembly and Mahakashyapa 'got it'. The early lineage can be explored in the Transmission of Light1 which takes us to the early Japanese ancestors. We are part of Soto Zen, one of the two main surviving schools in Japan (the other is Rinzai). Though in fact we have connection to lineages in both schools.
In the 1950s, Taizan Maezumi Roshi (then Sensei) went from Japan to the USA, and founded the Zen Centre of Los Angeles. At this point, although he had received Dharma transmission from his father, a Soto monk/priest, he continued to study with Yasutani Roshi and Koryu Roshi. Koryu Roshi was a lay Zen teacher in the Rinzai tradition. So Maezumi Roshi went through the Rinzai koan system.
Yasutani Roshi came from a very interesting lineage. His teacher, Harada Roshi, received transmission (with authority to teach) in the Soto school, but was dissatisfied with his own insight. He therefore signed up as a Rinzai monk and went through the whole Rinzai curriculum, and became authorised in that school too. His Dharma heir was Yasutani Roshi, who also gave transmission to Maezumi Roshi, who therefore inherited three Dharma streams.
The White Plum Asanga is the international umbrella organisation set up for all those schools of Zen which derive from Maezumi's work, and includes both the Wild Goose Zen Sangha and Stonewater Zen Sangha. Maezumi Roshi gave transmission to many students.
The Wild Goose Zen Sangha was set up by Rev. Patrick Kundo Eastman Roshi, who had received transmission from Father Robert Kennedy Roshi, SJ, who had in turn received it from Bernie Tetsugen Glassman Roshi, who was Maezumi's first Dharma heir.
Stonewater was set up by Dave Keizan Roshi, who, after many years studying with, and having been ordained by Dennis Genpo Merzel Roshi, Maezumi's second Dharma heir, switched teachers to Charles Tenshin Fletcher Roshi. Tenshin Roshi was another of Maezumi's Dharma heirs, and he gave Dharma transmission (shiho) and subsequently inka (senior teacher status) to Keizan.
Jeremy Ryokan Woodcock Sensei, having previously studied Zen with Father Ama Samy Roshi in India, became a student of Patrick Kundo in the WGZS, and Kundo Roshi gave Jeremy Ryokan transmission in 2016.
Soon after this Dheeresh switched teachers from Kundo Roshi to Ryokan Sensei. Jeremy Ryokan gave transmission to Dheeresh, giving him the name Shinkai ('Ocean of Fidelity') in 2020; shortly after this he left the WGZS and joined Stonewater. In January 2025 Dheeresh Shinkai took the same course.
For many years Dheeresh had been a student of Genpo Roshi, and has this in common with many of the teachers and students in Stonewater, including Keizan Roshi and Shinro Sensei, whom he has known since the late 1980s.
1. Thomas Cleary (transl.) (1990); Francis Dojun Cook (2003).