P eter Kellogg is an American businessman who made his fortune in stock market brokerage and specialist trading. He is the son of James Crane Kellogg III, a former chairman of the New York Stock Exchange. Following in his father's footsteps, Peter Kellogg embarked on a career in finance. He dropped out of college and joined his father's firm, which was a specialist on the floor of the American Stock Exchange. In 1973, he became a partner in the firm Spear, Leeds & Kellogg.

Spear, Leeds & Kellogg grew to become one of the largest specialist firms on the New York Stock Exchange, responsible for maintaining orderly markets in thousands of stocks. Kellogg and his partners built the firm into a dominant player in market making and brokerage services. In 2000, they sold the firm to Goldman Sachs for $6.5 billion in cash and stock, which made Kellogg a billionaire. Since the sale, he has maintained a low public profile, managing his wealth and engaging in philanthropy. He owns a large ranch in Wyoming and has invested in various businesses, including the re-insurance firm IAT.