The Dobro is an American brand of resonator guitar, currently owned by the Gibson Guitar Corporation. The Dobro was originally made by the Dopyera brothers when they formed the Dobro Manufacturing Company. Their design, with a single inverted resonator, was introduced in competition to the patented Tricone and biscuit designs produced by the National String Instrument Corporation. The Dobro name appeared on other instruments, notably electric lap steel guitars and solid body electric guitars and on other resonator instruments such as Safari resonator mandolins.Gibson Guitar Corporation acquired the Dobro trademark in 1994. Although the name Dobro is generically associated with the single-inverted-cone design, Gibson has announced that it would defend its right to exclusively use the name.