Jim Simons
Jim Simons.
  • Renaissance Technologies boosted its Tesla stake from 1,400 shares to 3.4 million last quarter.
  • The stock purchases lifted the value of RenTech's stake from under $400,000 to over $400 million.
  • Jim Simons' quantitative fund also ramped up its bets on Amazon and Apple in the period.

Renaissance Technologies boosted the size of its Tesla bet by more than 1,000-fold last quarter, making Elon Musk's automaker one of its largest holdings.