For years, @properties has sat atop Chicago residential real estate, fueling speculation about if and when they might aggressively expand outside Chicagoland.

On Wednesday, the brokerage announced perhaps its biggest move ever outside the Windy City, stating that they have acquired Christie’s International Real Estate, a New York City-based brokerage. The deal is set to close Dec. 1, and how much @properties paid to acquire Christie’s was not disclosed.

Christie’s is best known for their high-end auctions, but the brokerage has a “global network of approximately 900 real estate offices,” according to a press release announcing the deal. The offices are almost exclusively in pricey areas and span the globe with physical brokerage locations including Aspen, Colorado; Lima, Peru; Stockholm, Sweden; Costa Del Sol, Spain, and the Caribbean Island of Antigua.

Unclear, though, is what market share Christie’s has in its travelogue of locales. The company did not break down market share or revenue figures, beyond stating that is has done $500 billion worth of real estate transactions between 2016 and 2020.

Meanwhile, @properties ranks 8th on RealTrend’s third-party verified and self-reported list of top brokerages nationally by sales volume with $16.4 billion in 2020 from 32,359 transaction sides. The company is private and has said that it is profitable.

The brokerage was founded 2000 by Thad Wong and Mike Golden, who remain the companies’ co-CEO’s. In 2018, @properties announced that Quad-C, a Charlottesville, Virginia private equity firm was investing in the company, and that @properties would start a franchise network.

The network has grown fairly deliberately with locations in Detroit and Dallas, and investments in other brokerages including Ansley Atlanta. Also, @properties announced last year a mortgage loan joint venture with fellow Chicago company Guaranteed Rate.

As for the Christie’s deal, the New York brokerage will retain its branding but have its operations completely under @properties.

“The new business will retain the name Christie’s International Real Estate, will create one of the largest residential brokerage firms in the United States and will allow for further expansion across their global markets,” reads the press release.

Messages left with @properties and Christie’s were not immediately returned. The story will be updated with any comments from the companies beyond the press release.