The IOC approved the entry of 271 Russian athletes for the Rio de Janeiro Olympics on Thursday, meaning 70 percent of the country's original team will compete in the games after the scandal over state-sponsored doping.
Also Thursday, the IOC's rule barring Russian athletes with prior doping sanctions from competing in the games was rejected as "unenforceable" by an Olympic sports arbitration panel.
The International Olympic Committee announced the go-ahead for 271 Russian athletes on Thursday night, about 24 hours before the opening ceremony of the games.
The IOC recently rejected calls from anti-doping organizations to ban Russia's entire team following a report by a World Anti-Doping Agency investigator that detailed evidence of state-directed doping and cover-ups.
Instead, the IOC asked international federations to examine each individual Russian athlete to determine if they should be eligible to compete. The IOC set up a panel of three executive board members to make the final call, taking into account the advice of an independent sports arbitrator.
After the review, the IOC declared in Thursday's statement: "271 athletes will form the team entered by the Russian National Olympic Committee from the original entry list of 389 athletes."
Russian Olympic Committee president Alexander Zhukov told reporters earlier that 271 of his country's athletes had been cleared.
"We have good news for the fans of the Russian Olympic team," he said. "The majority of the sports have been admitted in full."
Several international federations announced separately Thursday that they had received the final approval for Russian entries in their events, including boxing, judo, equestrian, volleyball and golf.
Russia's track and field team remains barred following an earlier decision by the IAAF.