Police said the 31-year-old man lost his balance and fell to the courtyard of the East 74th Street building around 10:30 p.m. Sunday.
Mastronardi was the head of USD Exotic Derivatives at Vyapar Capital Market Partners.
The New York Post reports that the Department of Housing Preservation and Development will inspect all the windows in the building.
City law requires that all windows in apartments with children under the age of 10 have window guards.
HPD told the Post it had not received any complaints about the building.
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