Leonard M. Rosen, a founder of the Wachtell, Lipton, Rosen & Katz law firm who helped avert a New York City bankruptcy in 1975 and created a restructuring practice that would guide the U.S. through the 2008 mortgage crisis. Rosen, born Nov. 19, 1930, was a partner of the New York-based firm since 1965 when he, Martin Lipton, Herbert Wachtell and George Katz, all graduates of New York University School of Law, formed what was to become a premier U.S. deal, bankruptcy and restructuring law firm. He retired in 1997. Rosen oversaw a restructuring of New York City’s finances made more difficult by the refusal of Republican U.S. President Gerald Ford to order a bailout, a condition encapsulated in the famous New York Daily News headline “Ford to City: Drop Dead.” Rosen also worked as an adjunct professor at the NYU law school and was active in the Lymphoma Research Foundation and the Children’s Cause for Cancer Advocacy. Born in New York, Rosen graduated from the College of the City of New York in 1951 before earning his law degree from NYU in 1954, according to the Martindale-Hubbell Law Directory. He is survived by his wife, Phyllis; sons Adam, Steven and David; daughter Carol; and nine grandchildren, according to the firm.