Guru's largest transaction was the divestment of El Paso Electric holding. : Billionaire investor Mario Gabelli (Trades, Portfolio), leader of New York-based GAMCO Investors GBL , disclosed his third-quarter portfolio earlier this week. With the goal of generating long-term capital appreciation, the renowned guru and his team search for opportunities among undervalued stocks that have a catalyst for growth. Keeping these criteria in mind, Gabelli entered 55 new positions, sold out of 43 holdings and added to or trimmed a slew of other investments during the quarter. Notable trades included the divestment of El Paso Electric Co EE .