The shock rocker, 55, spent 20 hours last month at the Windsor Club of Glendale, a California nonprofit that provides meeting locations for Alcoholics Anonymous and families of alcoholics to "achieve a more meaningful life through recovery," according to the group's website.
A certificate of completion was filed by the Assistance League of Los Angeles with a New Hampshire court on January 30. Manson had to file proof of his service by February 4.
Manson, whose legal name is Brian Warner, pleaded no contest in September to the misdemeanour charge in Laconia, nearly 50km north of Concord, the state capital.
A no contest plea means Manson did not contest the charge and did not admit guilt.
He initially was charged with two misdemeanour counts of simple assault stemming from the encounter with the videographer at the Bank of New Hampshire Pavilion in Gilford on August 19, 2019. The second charge, alleging that he spit on the videographer, was dropped.
Manson also was fined. He needs to remain arrest-free and notify local police of any New Hampshire performances for two years.
Prosecutor Andrew Livernois had said it was his first offence and he had no prior record.
Manson initially pleaded not guilty to both charges in 2021. His lawyer had said that the type of filming the videographer was doing commonly exposes videographers to "incidental contact" with bodily fluids.
Manson emerged as a musical star in the mid-1990s, known as much for courting public controversy as for hit songs like The Beautiful People and hit albums like 1996's Antichrist Superstar and 1998's Mechanical Animals.
Last year, a California judge threw out key sections of Manson's lawsuit against his former fiancée, Westworld actor Evan Rachel Wood, claiming she fabricated public allegations that he sexually and physically abused her during their relationship and encouraged other women to do the same. He is appealing the ruling. The judge recently ruled that Manson cover Wood's legal fees, according to Rolling Stone.
Manson's lawsuit, filed last year, alleges that Wood and another woman named as a defendant, Illma Gore, defamed Manson, intentionally caused him emotional distress and derailed his career in music, TV and film.
Several women have sued Manson in recent years with allegations of sexual and other abuse. Most have been dismissed or settled, including a suit filed by Game of Thrones actor Esmé Bianco.
