Oman's Court of Cassation ordered Monday a retrial in the case of eight out of 11 activists sentenced to between six and 12 months in prison for taking part in protests in 2011.
The court ordered the appeals court, which had upheld the jail sentences, to re-examine their cases, but with a new panel.
The top court rejected appeals lodged by the other three activists, citing "procedural mistake", lawyer Qais al-Qassimi told AFP. He said their appeals will be filed again soon.
Qassimi said he will request bail for the eight defendants.
The 11 activists, including writers, boggers, a female lawyer and a female journalist are jailed in a prison outside Muscat.
They were part of a group of activists who staged last month a 15-day hunger strike until the supreme court agreed to examine their appeals.
Several groups of activists and bloggers are facing trials for taking part in pro-reform protests or defaming Sultan Qaboos, who has ruled the Gulf state for 42 years.
The usually calm Oman was hit by a wave of protests in 2011 demanding political reforms. Riot police dispersed the demonstrations with force.
Sultan Qaboos responded by reshuffling the cabinet and increasing the powers of the consultative assembly.