U.S. District Judge Thomas Zilly said in an order that REX -Real Estate Exchange Inc could depose Barton for up to three hours in the company's lawsuit filed in 2021 accusing Zillow and National Association of Realtors (NAR) of anticompetitive business practices.

Zillow's lawyers had opposed any questioning of Barton, who co-founded Zillow in 2005 and has served as CEO since 2019. Zillow reported $2 billion in revenue last year.

REX's lawsuit alleged Zillow in 2021 redesigned its consumer website in concert with NAR to "segregate, conceal and demote" home listings that were not part of NAR's member-operated multiple listing services. They comprise the databases showing residential real estate for sale in regions across the country.

The change allegedly caused views on REX's listings to "plummet," the company said.

REX wants to question Barton about Zillow's decision to join multiple listing services and also its move to buy houses and originate mortgages.

A Zillow spokesperson on Tuesday said the company doesn't comment on pending cases, and a representative from NAR had no immediate comment.

REX and its lawyers at Boies Schiller Flexner did not immediately respond to messages seeking comment.

Zillow and NAR both have denied liability and are contesting claims in the lawsuit.

Lawyers for Zillow dispute there was any agreement with NAR and deny that the website redesign harmed competition.

Zillow's chief industry development officer was due to be questioned on Thursday, and the company's vice president of industry development has a deposition scheduled in May.

The complaint is seeking unspecified monetary damages and an injunction "from continuing to engage in any anticompetitive conduct."

A trial is scheduled for Sept. 18.

The case is REX - Real Estate Exchange Inc v. Zillow Inc et al, U.S. District Court, Western District of Washington, 2:21-CV-00312-TSZ.

For REX: Stephen Zack and Carl Goldfarb of Boies Schiller Flexner; Darren McCarty of McCarty Law; and Mark Rosencrantz of Carney Badley Spellman

For Zillow: Jay Jurata of Dechert; and Aravind Swaminathan of Orrick Herrington & Sutcliffe

For NAR: Ethan Glass of Cooley; and Michael Bonanno of Quinn Emanuel Urquhart & Sullivan

Read more:

RealPage antitrust lawsuits over rent prices consolidated in Tennessee

U.S. real estate brokerages must face home sellers' class action over commissions

National Association of Realtors' antitrust challenge rejected by U.S. Supreme Court

(Reporting by Mike Scarcella; editing by Leigh Jones)

By Mike Scarcella