ents, while offering others supplemental assistance, help in special situations or customized in-house services. Tourmaline was founded in 2011 by Jonathan Goldstein, Daniel Groff, Aaron Hantman and Henry Higdon 3d, who earlier helped launch Williams Trading. The company has 36 staffers in Stamford, New York an

was founded in 2011 by a group of former Greenwich Prime Trading Group staffers: chief operating officer Daniel Dispigna; chief financial officer Jonathan Goldstein; compliance head and senior equity trader Ike Groff; derivatives-trading chief Aaron Hantman; and Henry Higdon 3d., who heads a London office. Som

was founded in 2011 by a group of former Greenwich Prime Wading Group staffers: chief operating officer Daniel Di spigna; chief financial officer Jonathan Goldstein; compliance head and senior equity trader Ike Grotf; derivatives-trading chief Aaron Hallman; and Henry Higdon 3d., who heads a London office. Som