Oracle inks $5.3 billion deal for Micros Systems E-mail Tweet Facebook Google Plus Linkedin Share icons by Ben Geier @FortuneMagazine June 23, 2014, 7:58 AM EDT Redwood, Calif.-based software giant Oracle is buying retail and hospitality software company Micros Systems for approximately $5.3 billion, or $4.6 billion net of cash. The firm, which has made several acquisitions over the past few years, is making its biggest purchase since it spent $7.4 billion to buy Sun Microsystems in 2010. Micros Systems’ main product is an Internet-connected cash register and the software that powers it. The is Oracle’s fifth acquisition so far in 2014, following purchases of LiveLOOK, GreenBytes, BlueKai and Corente. The software firm also made five purchases in 2013 and a whopping 11 in 2012.