Nope, Maxis originally created the Sims. Sims 1 still is, in my opinion, brilliant, even though I haven't gone back to playing it since Sims 3 and I'm sure the low graphics and no open neighbourhood would annoy me. But sims 1 was innovative, quirky, funny, and also open source as Maxis encouraged people to create items, clothing, etc. One of the good things that happened when EA bought Maxis is a lot of the team went to EA and carried on with the Sims series. In fact, the guy who originally designed and programmed death in Sims 1 is still there, working at EA and has done death in Sims 2 and 3. That's why death in Sims 3 is such a brilliant NPC, very funny and quirky as it retains the original Maxis humour.
Edit: Finished typing this after Hosfac sent in his reply. Following on from that what most people don't realise is that a good percentage of EA games are not designed by EA but only published.