The Kagyu Tradition, after the time of Marpa and Milarepa, branched into dozens of smaller schools with most over time becoming absorbed into Drugpa, Karma Kamtsang, Taglung and Drigung. In modern times the Drugpa Kagyu became the largest with the most followers, second in numbers is the Karma Kamtsang. The Nedo and Surmang are sub-schools of the Karma Kamtsang. In the 19th century Jamgon Kongtrul partially revived the Shangpa Kagyu Tradition (unrelated to Marpa Kagyu) primarily based on the teachings descending through the Jonang tradition and the writings of the famous 16/17th century teacher Taranata.
"The Kagyud Tradition developed from the teachings of Naropa and Maitrepa. The main founders of all the sects of the Kagyud are the three Great Masters: Marpa, Milarepa and Gampopa. From these three Masters the Kagyud Lineage scattered into the four major and eight minor Lineages. It was from Gampopa's disciple, Phagmo Drupa that most of these lineages of the Kagyud Tradition came, spreading in many different directions. Presently there are four which have not faded and still exist: the Karma Kagyud, Drukpa Kagyud, Drigung Kagyud and Taglung Kagyud. The Dharma lineages of the others have become very subtle or thin (having mostly been absorbed into larger lineages)."