It was Westbrook's 16th technical foul of the season, which would have resulted in an automatic one-game suspension.
This is Westbrook's second technical foul in the last seven games that was rescinded by the league after the fact. A technical he received on April 5 against Houston stood as his 15th of the season, but techs at Phoenix on March 29 and again Sunday night at Indiana were later ruled incorrect by the league office.
League rules state that players receive a one-game suspension starting with their 16th technical foul of the season and every other tech thereafter, with the slate wiped clean when the playoffs begin.
Thunder coach Scott Brooks said Sunday that he was "confident" the league would rescind the latest technical against Westbrook, who scored a career-high 54 points in Oklahoma City's 116-104 loss to Indiana.
The loss dropped the Thunder (43-37) into a tie with the Pelicans (43-37) for the eighth and final playoff spot in the Western Conference. New Orleans owns the tiebreaker, and both teams have two games remaining.
Westbrook, the All-Star Game MVP, is averaging 27.9 points per game this season and has carried the Thunder since Durant was ruled out for the season with a broken bone in his right foot.
He has 11 triple-doubles this season, the most by any player since 2007-08, and ranks fourth in the league in assists (8.6 per game) and second in steals (2.1). He was the Western Conference Player of the Month in February and March.
ESPN.com's Royce Young and The Associated Press contributed to this report.