Valeant Pharmaceuticals International Inc (VRX.TO) said on Thursday its former CEO Michael Pearson remains a significant shareholder of the Canadian drugmaker.

Valeant said Pearson exercised options to sell about 4.4 million shares apart from selling about 411,000 shares in June and July.

Pearson, who was replaced by Joseph Papa in May, still holds more than 3.5 million shares and is required to hold 1 million shares for two years following employment termination.

The company had 343 million shares outstanding as of June 2, according to a regulatory filing.

Pearson's share sale was to satisfy tax obligations with respect to the 2015 margin sale conducted by Goldman Sachs and for additional liquidity, the company said.

"While I trimmed my ownership position for personal reasons, I plan on holding my remaining shares until the company recovers and returns to being traded on fundamentals," Pearson said in a statement.

Valeant has been under intense scrutiny for its business and accounting practices, sending its shares plummeting 92 per cent from the record high of $263.81 it touched last August.