For further information, you might want to try news:rec.games.video.atari, I.C. When, or The History of Home Video Games Homepage.
On July 30, 1996, Atari was sold to JTS Corporation. Read Did you hear anyone say "Goodbye"? to find out more.
Subsequently, on February 23, 1998, JTS re-sold nearly all of Atari's assets to to HIACXI, Corp. ("HIAC"), a wholly-owned subsidiary of Hasbro Interactive, Inc. Read the SEC filing for details on the deal.
Put the 7800 back with the dust and cobwebs.