Ruane, Cunniff & Goldfarb Inc, the investment firm that runs the Sequoia Fund and once the largest shareholder of Valeant Pharmaceuticals International Inc, said it exited its position in the embattled Canadian drugmaker by mid-June.

Valeant has been under intense scrutiny for its business and accounting practices, sending its shares plummeting 91 per cent from the record high of $263.81 it touched last August.

"Valeant was our largest position to start the year and its 80 per cent decline through June 30 badly penalized our results," Sequoia Fund said in a letter dated July 12.

Ruane, Cunniff & Goldfarb was sued earlier this year by shareholders, who claimed it recklessly took a huge stake in Valeant, causing more than $2 billion in losses.