The patent, filed with remarkably prescient timing, covered 'the method of, and apparatus for, transmitting vocal or other sounds telegraphically.' Bell would not actually speak the famous words 'Mr. Watson, come here' through a working device until three days later. The patent later became one of the most valuable and litigated in American history, spawning hundreds of lawsuits.
Alexander Graham Bell filed his patent application on Valentine's Day, February 14, 1876, arriving at the patent office mere hours before a rival inventor, Elisha Gray, submitted a similar notice for a telephone-like device. The U.S. Patent Office granted Bell's application on March 7, though Bell had not yet built a device that actually worked. Three days later, on March 10, he achieved the first successful transmission of intelligible speech, telling his assistant Thomas Watson in the next room, 'Mr. Watson, come here, I want to see you.'
The patent, number 174,465, is often called the most valuable single patent ever issued. It triggered decades of litigation, with over 600 lawsuits filed against Bell and his successor company, the Bell Telephone Company, which grew into AT&T. Critics have long argued that Bell's application contained suspicious similarities to Gray's notes, fueling conspiracy theories that persist to this day. Regardless of the controversy, the patent laid the legal foundation for a communications empire that would shape the 20th century.