Short answers, pulled from the story.
Madhouse was established in 1972 by a group of animators including Masao Maruyama, Osamu Dezaki, and Yoshiaki Kawajiri. They secured funding from Yutaka Fujioka to begin operations after leaving Mushi Production.
Nippon TV acquired full control of Madhouse by March 2014 when they purchased all remaining shares from Index Corporation. This transaction raised Nippon TV's stake to 95% and gave them near-total ownership of the studio.
Satoshi Kon created four feature films for Madhouse: Perfect Blue, Millennium Actress, Tokyo Godfathers, and Paprika. He was preparing his fifth film called Dreaming Machine when he died in 2010.
Madhouse partnered with Warner Bros. Animation and Marvel Animation throughout the 2000s and 2010s to produce adaptations like Blade, Iron Man, Wolverine, X-Men, Black Widow, and Punisher. The studio also collaborated with Disney+ on an Avengers adaptation and worked with Studio Ghibli on Spirited Away and Howl's Moving Castle.
Sanae Tashiro became president and CEO of Madhouse in 2021 after serving as a board member alongside Yuuzou Kuwahara and Toshiya Gotou. Masao Maruyama had previously served as COO until 2011 before stepping down from leadership roles.