Millennium Partners Discloses Data Breach Impacting Customers and Employees New York-based real estate firm Millennium Partners (formerly Millennium Partners Management LLC) reported a data breach affecting the personal information of customers and employees. The incident was detected on April 27, 2026, after an unauthorized party accessed the company’s systems between April 24 and April 26, 2026, causing a network disruption. The ransomware group The Gentlemen claimed responsibility for the attack, announcing on May 5, 2026, via the dark web that they had exfiltrated data and threatened to publish it within eight to nine days. By July 9, 2026, Millennium Partners confirmed that sensitive data potentially including Social Security numbers had been accessed and acquired by the attackers. In response, the company set up a toll-free call center (1-800-405-6108) through TransUnion, operating from 8 a.m. to 8 p.m. ET, Monday through Friday, to assist affected individuals. The breach underscores the ongoing risks of ransomware attacks targeting corporate networks and the exposure of sensitive personal data.