Artur will be staying with Columbus Crew SC after the MLS club retained the midfielder's services in a permanent transfer.
After spending 2016 on loan with Columbus, the 21-year-old Brazilian posted a tweet last week to thank fans, seemingly drawing an end to his time in the U.S.
Reports said Artur's parent club had rejected Columbus' offer of $1.5 million for half of Artur's rights, but Crew SC continued to negotiate and completed the move on Wednesday.
"Artur was one of the most promising young players in MLS last season and completing his transfer from Sao Paulo FC was one of our priorities this offseason," Crew coach Gregg Berhalter said in a statement.
"We are happy that he has committed his future to the club and we look forward to beginning our work together on a successful 2018 campaign."
Artur made 19 starts for Columbus this season and had three assists in 24 total appereances.