<P> The Oklahoma City Thunder are an American professional basketball team based in Oklahoma City, Oklahoma . The Thunder competes in the National Basketball Association (NBA) as a member of the league's Western Conference Northwest Division . The team plays its home games at Chesapeake Energy Arena . </P> <P> The Thunder's NBA G League affiliate is the Oklahoma City Blue, which it owns . The Thunder are the only team in the major professional North American sports leagues based in the state of Oklahoma . </P> <P> The team was originally established as the Seattle SuperSonics, an expansion team that joined the NBA for the 1967--68 season . The SuperSonics moved in 2008 after a settlement was reached between the ownership group led by Clay Bennett and lawmakers in Seattle, Washington following a lawsuit . In Seattle, the SuperSonics qualified for the NBA playoffs 22 times, won their division six times, and won the 1979 NBA Championship . In Oklahoma City, the Thunder qualified for their first playoff berth during the 2009--10 season . They won their first division title as the Thunder in the 2010--11 season and their first Western Conference championship as the Thunder in the 2011--12 season, appearing in the NBA Finals for the fourth time in franchise history and first since 1996, when the club was based in Seattle . </P> <P> The Thunder's previous incarnation, the Seattle SuperSonics, were formed in 1967 . In their 41 seasons in Seattle, the SuperSonics compiled a 1745--1585 (. 524) win--loss record in the regular season and went 107--110 (. 493) in the playoffs . The franchise's titles include three Western Conference championships and one NBA title in 1979 . </P>

When did the okc thunder become a team
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