Fun fact: a bunch of animators from the studio went on to form Studio Ghibli:

Topcraft Co., Ltd. (株式会社トップクラフト Kabushiki-gaisha Toppukurafuto, also written as “Top Craft”) was an animation studio established in 1972, by former Toei Animation producer Toru Hara, and located in Tokyo, Japan. It was famous for the production of Nausicaä of the Valley of the Wind. Topcraft is well known for its collaboration for hand-drawn animation titles by Rankin/Bass Productions (New York City, US). Together, they produced several well-known animated films, including The Hobbit and “The Return of the King”. The studio served as a precursor to Studio Ghibli, another renowned Japanese animation studio.