Want to buy a piece of the Empire State Building? Interested investors are one step closer. The Malkin family disclosed plans to create a publicly traded real estate company that would include the 102-story skyscraper at Fifth Avenue and 34th Street, according to papers filed Tuesday with the Securities and Exchange Commission. The plans were first reported in April. Two other buildings controlled by Anthony E. Malkin and his father, Peter L. Malkin — 1 Grand Central Place, a 55-story, 1.3-million-square-foot building across 42nd Street from Grand Central Terminal, and a 26-story building at 250 West 57th Street — would be part of the publicly traded real estate company.