American Bell Telephone Company

The Bell Telephone Company, a common law , was organized in Boston, Massachusetts on July 9, 1877, by Alexander Graham Bell's father-in-law Gardiner Greene Hubbard, who also helped organize a sister company — the New England Telephone and Telegraph Company. The Bell Telephone Company was started on the basis of holding "potentially valuable patents", principally Bell's master telephone patent #174465.

The two companies merged on February 17, 1879, to form two new entities, the National Bell Telephone Company of Boston, and the International Bell Telephone Company, soon after established by Hubbard and which became headquartered in Brussels, Belgium.Theodore Vail then took over its operations at that point, becoming a central figure in its rapid growth and commercial success.

The National Bell Telephone Company merged with American Speaking Telephone Company on March 20, 1880, to form the American Bell Telephone Company, also of Boston, Massachusetts.

Upon its inception, the Bell Telephone Company was organized with Hubbard as "trustee", although he was additionally its de facto president, since he also controlled his daughter's shares by power of attorney, and with Thomas Sanders, its principal financial backer, as treasurer. The American Bell Telephone Company evolved into the American Telephone & Telegraph Company (AT&T), at times the world's largest telephone company.

The Bell Patent Association (February 27, 1875 – July 9, 1877, a name later assigned by historians), was not a corporate entity but a trusteeship and a partnership. It was established verbally in 1874 to be the holders of the patents produced by Alexander Graham Bell and his assistant Thomas Watson.

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