David Einhorn sees 'enormous tech bubble,' adds a few stocks to portfolio

David Einhorn
Andrew Harrer | Bloomberg | Getty Images

(This story is for CNBC Pro subscribers only.)

Greenlight Capital's David Einhorn sent a dire warning on an "enormous" speculative bubble in technology stocks, saying the hedge fund has initiated a number of short positions on "second-tier" names and recent high-flying IPOs in the space.

The fund also added some long positions.