The Ducks staff was informed Thursday afternoon and relayed the news in a text to ESPN.com.
If Kazemi didn't receive the waiver, his plan was to sit out the year rather than declare for the NBA draft or seek a contract overseas, according to a source.
A transfer from Rice who had been practicing with Oregon, Kazemi will be eligible to play Friday night against Vanderbilt.
He missed Oregon's first two games.
Kazemi, the first Iranian-born college basketball player in Division I, averaged 12.4 points and 10.3 rebounds for Rice last season and would have been one of the leading contenders for Conference USA player of the year honors had he returned to the Owls.
Kazemi gives the Ducks an immediate lift inside and should propel Oregon into contention for a top-four finish in the Pac-12.
Kazemi becomes the second Rice transfer to gain immediate eligibility in the Pac-12.
Kazemi and Oraby were two of six players who left the Owls after last season.