One of the city’s largest residential brokerages, Prudential Douglas Elliman, cried foul against a small competitor on Monday.

Elliman filed a complaint against brokers Saunders & Associates claiming that it illegally registered various Internet domain names associated with Prudential Douglas Elliman so that customers searching online are automatically directed to Saunders’ website.

As a result, Elliman is seeking damages as well as a court order that forbids Saunders from “engaging in any further malicious and anti-commercial activity directed at plaintiff, including the registration of any Internet domain names associated with plaintiff,” according to the filing. The filing also alleged that Saunders stole the identities of several well-known and high-producing Elliman real estate brokers so that any customers searching for them online are automatically directed to Saunders’ websites.

“This is an action seeking to reveal a gross violation of Prudential Douglas Elliman’s proprietary rights through the sly and dishonest registration of domain names by Saunders & Associates,” said Stanley Arkin of the law firm of Arkin Kaplan Rice, who represents Prudential Douglas Elliman, in a statement.

Andrew Saunders, founder and president of Saunders & Associates, did not receive a copy of the complaint. However, Mr. Saunders said he is not aware of owning any domain names that should not belong to his firm. “If we did own names that are inappropriate, we will give them back immediately,” he said.

Mr. Saunders acknowledges that his firm owns and has registered 3,000 domain names that might result in high page ranking when certain phrases are entered into Google for searches. According to the Elliman complaint, the “defendants’ marketing strategy is marked by nefarious, anti-competitive and illegal conduct.”

The complaint also noted published news reports last month in which Mr. Saunders admitted misconduct in registering two domain names that belonged to brokers registered at Elliman and at The Corcoran Group. Mr. Saunders said he transferred ownership of those domain names back within a week of finding out about the act and claimed “an overzealous staffer” was responsible for inappropriately buying those names.

The complaint claims that Saunders has not “relinquished ownership and control over all of the Internet domain names acquired to further their scheme. This includes at least one domain name closely associated with defendants’ competition, which continues to direct Internet browsers to a website registered and controlled by defendants.”

Saunders & Associates, a two-and-a-half-year-old brokerage with 70 brokers, recently opened a second office in Southampton on Long Island and competes directly against Prudential Douglas Elliman in the Hamptons.