Mark Stone was the bass guitar player in a band called Mammoth from 1972–1974. Mammoth also featured Eddie Van Halen (lead vocals and guitar) and Alex Van Halen (drums). ^[1] In early 1974 vocalist David Lee Roth joined the band, who shortly thereafter changed their name to Van Halen. By around mid 1974, the group felt that Stone's commitment to school outweighed his interests in pursuing music professionally, and decided to look for another bass player. Michael Anthony, from the Pasadena-area band Snake, was chosen as Stone's replacement. Stone remained on good terms with his former bandmates, and attended Eddie Van Halen's marriage to Valerie Bertinelli in 1981.

Though Stone has never been credited with any songwriting for Van Halen, recordings of early Van Halen originals dating to c. 1974 have surfaced which purportedly feature Stone on bass.

Over the years there has been increasing fan interest in the early history of Van Halen, and Stone's tenure with the group.

During the transitional period after the joining of David Lee Roth, with Stone playing bass, the band relied predominantly on cover songs for their live set, but were also in the early phase of writing and performing original compositions.

It is not known to what degree Stone was involved in the composition of these early Van Halen originals, although he is said to have played on the band's first demo recordings that were given to Michael Anthony to learn for his formal audition with the group.

Stone is still currently living in Sierra Madre. He appeared in the DVD Van Halen Story – The Early Years, released in 2003 by E1 Entertainment. In 2015, Stone was a guest with Fan Halen, a tribute band mimicking the early Roth-era lineup of Van Halen. ^[2]