Mark Epstein

Mark Epstein (born c. 1955), businessman and real estate developer. Younger brother of Jeffrey Epstein. Operated real estate businesses in New York and managed properties connected to his brother's activities. Testified before the grand jury in Jeffrey Epstein's criminal cases. Mark Epstein's Manhattan apartment at 301 East 66th Street was allegedly used by Jeffrey Epstein for meetings and encounters — Epstein maintained a key and access to the property. Listed in Epstein's contact directory. Appeared as a witness in multiple legal proceedings related to Jeffrey Epstein. While not accused of participating in criminal activity himself, his proximity to Jeffrey Epstein's operations and property connections make him a significant contextual figure. Classified as Tier 4 (Associated).

Classification basis: Brother of Jeffrey Epstein. Property connections — apartment allegedly used by Jeffrey Epstein. Grand jury testimony. No evidence of criminal participation.