U.S.-based tobacco companies Philip Morris International Inc. and Altria Group Inc. (MO) pared gains as a lawsuit seeking as much as C$27 billion ($27.2 billion) from Canada’s three biggest cigarette makers went to trial.

New York-based Philip Morris, owner of Canadian tobacco company Rothmans Benson & Hedges Inc., a defendant in the trial, slipped 0.10 percent to $84.54 at 4:15 p.m. in New York. The stock had risen as much as 1.1 percent earlier in the day. Richmond, Virginia-based Altria, which isn’t a defendant, fell 0.10 percent to $30.44.

The Quebec Superior Court in Montreal is hearing two class- action lawsuits by smokers representing people seeking financial compensation for harmful effects of smoking, the Canadian Cancer Society said today in a statement.

Canada’s government has “legalized, heavily regulated and taxed” the country’s tobacco industry, according to a statement from Imperial Tobacco Canada, which called the lawsuits “an opportunistic cash grab.”

Imperial Tobacco, a subsidiary of British American Tobacco Plc (BATS), is a defendant along with JTI-MacDonald Corp., owned by Japan Tobacco Inc. (2914), and Rothmans.

To contact the reporter on this story: Chris Burritt in Greensboro at cburritt@bloomberg.net

To contact the editor responsible for this story: Robin Ajello at rajello@bloomberg.net