The Ontario Securities Commission has charged Andrew Rankin, a former executive with RBC Dominion Securities, with 10 counts of insider trading and 10 counts of "tipping."

The charges laid Wednesday by the securities commission are part of the highest-profile investigation into insider trading in Canadian history, involving almost $2 million in illicit gains and the country's largest investment dealer.

Rankin, who was managing director of the brokerage's mergers and acquisitions group from 1999 to 2001, was fired following the firm's internal investigation of "suspicious" trading practices.

Daniel Duic, a longtime friend of Rankin's, has been charged with 10 counts of insider trading.

Canada's largest securities commission alleges that Rankin illegally tipped Duic to pending mergers and acquisitions before they were publicly known.

"Rankin had knowledge of these transactions in advance of their being publicly announced in that RBC DS was acting as an advisor to one of the parties or proposed parties in each of the merger or acquisition transactions," the commission said in its statement of allegations.

The securities commission alleges that Duic bought and sold shares and/or options in 10 companies, including Canadian Pacific and Moffat Communications, using a pseudonym and through offshore accounts in several jurisdictions.

Duic is accused of pocketing realized and unrealized profits of almost $1.9 million after the securities increased in value following the release of the merger and acquisition news.

Duic has reached a tentative settlement with the securities commission's enforcement staff. A hearing will be held March 3 to determine if the commission should approve the settlement.

Rankin has been ordered to stand trial in Ontario provincial court. A date for the trial has not been set. If convicted, Rankin faces a maximum penalty of two years in prison and a fine of $1 million.