The Grimsaem animation studio is also known as Sunwoo Entertainment because it was spun off of the Sunwoo after years of success. The company was established in the year of 1979, and it is known to be a South Korean animation studio. It is claimed that the studio had been around since the year of 1974 though. They began by working with South Korean productions, but they eventually moved to work with Disney about ten years later. Now they are considered to be one of the more popular overseas animation studios. Once Sunwoo became successful, the new and different companies that were born from it included Anivision, Sunwoo Digital, and of course Grimseam. In addition to working along with Disney, Sunwoo and its smaller studios have also worked for Universal, Cookie Jar Entertainment, 20th Century Fox, and Nickelodeon in the years following. In the year of 2000, all of the companies that were broken away from Sunwoo ended back up in the Sunwoo Entertainment studio.