In February, police notified the Svenska Spel of reports of suspected fraud involving poker robots or "bots".
Robots or "bots" are computer programs designed to play the game of poker against human opponents or other computer opponents.
"There is suspected gambling revenues from other gaming companies, but the criminal investigation concerns only Svenska Spel," says prosecutor Henrik Olik to Swedish Radio News.
Five people identified as being mainly involved, deny committing any crime.
According to Svenska Spel, the five accused have created computer bot software which enables them to take home big profits in online poker without playing themselves, which the company says is cheating.
Svenska Spel says the poker bots operated in stakes ranging from $0.25/$0.50 up to $2.50/$5.00. The bots have developed to the stage where they can beat weaker players but not the better, higher stake poker players.