Sons of Silence Motorcycle Club (SOSMC) is a one-percentermotorcycle club that was founded in Niwot, Colorado in the United States in 1966. The first chapter outside of Colorado was the Iowa chapter which was founded in 1968. There are now American chapters in Arkansas, Florida, Illinois, Indiana, Kansas, Kentucky, Louisiana, Minnesota, Mississippi, Missouri, North Dakota, South Dakota, Tennessee, Utah and Wyoming. The first foreign chapter was founded in Munich, Germany in 1998. In 2001, more German chapters were founded in Freising, Gangkofen and Nürnberg. In November 2007, a Viernheim chapter was founded.
The Sons of Silence's logo is an American eagle superimposed over the letter "A" (similar to, and taken from, the Anheuser-Busch logo) flying under an arch and their motto is "donec mors non separat ", Latin for "until death separates us". The logo is embroidered onto the back of all members' jackets or vests.
On October 9, 1999, 37 Sons of Silence members were arrested on drug trafficking and illegal weapons charges after one of Denver's largest federal undercover operations. The Bureau of Alcohol, Tobacco and Firearms raided a number of homes and properties in Colorado Springs and Fort Collins, and seized 20 pounds of methamphetamine, 35 guns, four hand grenades, two suppressors, cash and motorcycles. The investigation began in 1997 and involved two undercover agents infiltrating the club. The club was featured in a 2009 episode of Gangland, which included interviews with one of the undercover agents who infiltrated the club.