4D Interactive Systems, Inc. was a company based in St. Paul, Minnesota, started by Dan Nicholson with David Wesely, Dungeons & Dragons co-creator Dave Arneson, and David Megarry. It was incorporated on February 14, 1978, and dissolved on April 7, 2006.
The company was not limited to video games, they worked on the medical, industrial, and educational fields as well.
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