The inventor Antonio Meucci filed a patent caveat for a telephone device in 1871. But having exhausted most of his life's savings in pursuing his work, Meucci was unable to renew his caveat after 1874.
In 1876, Alexander Graham Bell, who conducted experiments in the same laboratory where Meucci's materials had been stored (!), was granted a patent and was thereafter credited with inventing the telephone.
In 2002 the US Congress finally recognized Antonio Meucci as the true inventor of the telephone.