Billionaire investor Carl Icahn now holds a 6.9% stake in real estate operator Insignia Financial Group Inc. (NYSE: IFS), according to a Securities and Exchange Commission filing on Monday. IFS owns Insignia/ESG, one of the nation’s leading real estate services firms.

The investor paid more than $12 million for roughly 1.6 million shares of the New York-based real estate brokerage firm.

High River Limited Partnership, one of Icahn’s investment vehicles, bought 611,200 Insignia shares between Nov. 13 and Nov. 29 at prices ranging from $5.86 to $7.49 per share to add to the previous holdings, per the filing. On Nov. 26, Icahn bought 331,400 shares of the stock at $7.04 per share.

Insignia shares have ranged from $5.25 to $11.82 in the past 52 weeks. As of Dec. 4, the stock was trading at $7.80 per share.