RELX Group is buying the Silicon Valley-based fraud detection service ThreatMetrix Inc. for 580 million pounds, roughly $814 million at current exchange rates.

ThreatMetrix assesses risk for online transactions in real time and offers payment authentication services for card-not-present transactions, as well as other services. Online retail clients include apparel e-retailer Bonobos, No. 232 in the Internet Retailer Top 1000, and camera manufacturer GoPro Inc., No. 355.

RELX Group (formerly Reed Elsevier) says it expects to complete the purchase by the end of June and that ThreatMetrix will be part of its growing LexisNexis Risk Solutions group.

ThreatMetrix and LexisNexis Risk Solutions have been working together for about two years. LexisNexis Risk Solutions included ThreatMetrix’s device intelligence services in its Risk Defense Platform.

ThreatMetrix launched in 2005 and raised about $84 million across several funding rounds since then, including $30 million in “mezzanine financing” in 2016 from Silicon Valley Bank. Mezzanine financing is a way to finance debt. ThreatMetrix says it has 5,000 customers spanning 35,000 websites.