Government regulators in Canada are poised to open a formal investigation into whether Google is abusing its dominance of the Internet search market to stifle competition and drive up digital advertising prices.

Canada's Competition Bureau indicated in a filing made in an Ottawa federal court earlier this week that it suspects that Google has been breaking the country's antitrust laws. Regulators are seeking a court order that would require Google's Canadian subsidiary to furnish antitrust investigators with internal company records.

Based on its preliminary findings, the commission "has reason to believe that the manner in which Google operates its search engine and search-advertising platforms ... amount to an abuse of a dominant position," wrote Mark MacLachlan, a senior competition law office for the agency.

Among other things, Canadian regulators believe Google has been giving preferential treatment to its own services in its influential search rankings to thwart potential rivals. Investigators are also examining whether Google's partnerships with other websites and device makers are making it more difficult for rival products to compete. Those concerns mirror issues that have already been raised by regulators in other countries.

"We will work cooperatively with the Competition Bureau to answer any questions they may have," said Google spokeswoman Leslie Church. The Mountain View, Calif., company has consistently defended its search rankings as a form or free speech and denied doing anything to squash competition.

Canada's Competition Bureau didn't immediately respond to a request for comment late Friday.

Regulatory headaches have become a recurring pain for Google during the past few years. The company has cemented its position as the Internet's main gateway while expanding into other areas such as online video, digital maps, business reviews and shopping that have gained traction with the assistance of a search engine that processes about two out of every three online queries..

The US Federal Trade Commission closed an extensive antitrust investigation into Google's methods earlier this year without finding any wrongdoing. Attorneys general in various states are still scrutinizing Google for possible anti-competitive behaviour, but none have taken action against the company.

A broad investigation by European regulators remains open, though Google has offered to tweak the way to it ranks some of its search results in an attempt to resolve the inquiry without facing financial penalties.

Canada opened an informal inquiry into Google's business practices in May, according to this week's filing. The probe hadn't been previously disclosed.