There is not really much if anything left of the original Atari. That pretty much failed after the video game crash in 1983, and was split in two, and bounced around various owners.
The Atari that brought out the Atari ST etc. was one of those, but that pretty much failed and Tramiel merged it into JTS and later sold the remains to Hasbro which then sold it to Infogrames Entertainment. The current Atari Inc. used to be Infogrames, and just licensed the name. Infogrames Entertainment itself then renamed itself to Atari SA.
The other part of the original Atari, Atari Games Inc. failed in 2003. The intellectual property of that division is as far as I know now owned by Warner.
The Atari that brought out the Atari ST etc. was one of those, but that pretty much failed and Tramiel merged it into JTS and later sold the remains to Hasbro which then sold it to Infogrames Entertainment. The current Atari Inc. used to be Infogrames, and just licensed the name. Infogrames Entertainment itself then renamed itself to Atari SA.
The other part of the original Atari, Atari Games Inc. failed in 2003. The intellectual property of that division is as far as I know now owned by Warner.