Sleeping Dogs sold 172,000 units during the month of August, according to NPD figures given to Joystiq.
Square Enix's well-reviewed action title launched in the US on the same day as THQ's equally well-received Darksiders II. The THQ game came out on top in the US, moving 247,000 copies to take the No.1 spot in the August chart.
Sales of Sleeping Dogs on PC are not included as the game wasn't released in boxed retail form in the US, being available on digital download stores only.
In the UK Sleeping Dogs has dominated the sales chart since its release, sitting at the top for three out of four weeks, whereas Darksiders II is currently struggling to remain in the top 10.