Former BetOnSports boss David Carruthers has been sentenced to 33 months in prison for his role in the business offering online gambling to Americans.
He was arrested in Texas in July 2006, and had agreed to cooperate with US authorities for leniency.
The sentencing "concludes a lengthy investigative and prosecution effort by several law enforcement agencies," the Justice Department said in a statement.
BetOnSports was founded in 1995, and by the time of its float on London’s Alternative Index Market (AIM) in 2004 had nearly one million registered customers. The company ceased operations in 2006 following Carruthers’ arrest and the suspension of trading in the US.
Carruthers sentencing follows that of BetOnSports founder Gary Kaplan, who was jailed for more than four years and ordered to hand over more than $43m (£26m) in illegal earnings in November for his part in the business, after earlier admitting conspiring to violate the federal racketeering and other US laws at the US District Court in St. Louis in August.
The plea was widely expected after Kaplan was left as the only executive of the sportsbook facing trial after his brother, Neil Kaplan, and sister Lori Kaplan Multz pleaded guilty to racketeering, conspiracy and the illegal transmission of bets in June 2009, in what was expected to have been a prelude to a deal with Kaplan himself, with former colleague Penelope Tucker pleaded guilty to one count of aiding and abetting wire wager act violations along with the pair.