Lawyers for the cook filed a suit against Danny Lavy for 2.25 million Canadian dollars (£1.4m) in lost license fees after the two parted ways. The suit includes 500,000 Canadian dollars in damages for alleged defamation.
Neither a spokesman for the restaurant nor Mr Lavy were immediately available for comment.
In February, Mr Lavy cancelled his contract with Ramsay and changed the restaurant's name from Laurier Gordon Ramsay to The Laurier 1936.
The lawsuit said the agreement was binding for 10 years but could be dissolved if the restaurant declared bankruptcy or did not make at least four million US dollars in net sales in the first five years. The lawsuit argues Ramsay met his obligations under the licensing agreement.
According to documents filed in court, Ramsay said Mr Lavy defamed him in announcing the split in an article published in the Montreal Gazette on February 16.
Mr Lavy is quoted in the lawsuit as telling the Gazette that Ramsay was "too busy to come to the restaurant" and that the celebrity chef's team did nothing the restaurant's staff could not have done on its own.
He is also quoted as saying Ramsay did not understand the owners' vision, gave only minor tweaks to the menu without providing a "wow" dish and did not do promotional efforts such as appearing on a popular TV talk show.
Ramsay's lawsuit calls the comments "false and defamatory".