The supplier has said in its lawsuit Sylebra is being investigated by more than 24 US and international gaming authorities, according to CDC Gaming Reports.
The Hong Kong-based firm has refused to comply with requests for information and disclosure submissions for suitability by regulatory bodies in the industry.
The lawsuit said investigators found Sylebra owns a significant stake in a Russian company with alleged ties to illegal gaming, money laundering and financial support of terrorist organisations.
A spokesperson for Scientific Games, Susan Cartwright, is reported to have said: "Scientific Games takes very seriously our obligation to maintain the highest standard of integrity and transparency with our regulators in Nevada, across the United States and around the world.
"As part of these efforts, we must be assured of the suitability of our major investors."
Sylebra owns more than 8.6 million shares of Scientific Games and has been an investor in the company for four years.