Qatar Airways already has a stake in Air Italy (49%), IAG (20%), LATAM (10%) and Cathay Pacific (9.99%). They have now bought a 5% stake in China Southern Airlines.
China Southern, one of the biggest Chinese carriers, is exiting SkyTeam. Word is just out that they are not going to renew their contract with SkyTeam on January 1, 2019 and will work on the exit formalities through 2019.