Matt O'Brien (born 22 July 1981) is a New Zealand-born Australian professional rugby union referee.
He has officiated on the IRB Sevens World Series circuit since 2011 and was appointed to the Super Rugby referees panel for 2014 and 2015.
He studied pharmacy at the University of Otago where he played as a winger on the University's rugby team in the early 2000s, before he moved to the Gold Coast in Australia and established a pharmacy business.
He was appointed to the IRB Sevens World Series in 2011, and was the referee in three finals matches.
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