15:39 On January 2, 1882, the Standard Oil Trust Agreement was formally signed, consolidating more than 40 separate oil-related companies under a single holding trust controlled by John D. Rockefeller and his associates. This structure allowed centralized control over refining, transportation, marketing, and pricing across much of the U.S. petroleum industry. At its peak, Standard Oil controlled roughly 85–90% of U.S. oil refining capacity, making it one of the most powerful industrial organizations in American history. The trust also owned or influenced thousands of miles of pipelines, rail tank cars, storage facilities, and export terminals, enabling it to reduce costs while squeezing competitors out of the market. The creation of the trust reshaped American business practices and directly influenced U.S. antitrust policy.