Hong Kong's top court has thrown out jail terms against three leaders of the 2014 pro-democracy "Umbrella" protests.
It reverses an earlier court appeal that saw Joshua Wong, 21, Nathan Law, 24, and Alex Chow, 27, being handed jail terms for unlawful assembly.
Their jail sentences attracted international attention, with rights groups accusing the government of cracking down on political protesters.
The 2014 protests paralysed parts of central Hong Kong for several weeks.
Wong, Law and Chow became the public face of the protests, which called for fully democratic elections for Hong Kong's leadership.
The sit-in became known as the "Umbrella movement" after protesters used umbrellas to shield themselves from tear gas fired by police.
The trio were convicted of unlawful assembly over an incident that helped trigger the mass protests.
Wong and Law were initially handed community service terms, while Chow was given a suspended jail term, in 2016.
However, in an unusual move, the Hong Kong government appealed against the sentences, arguing that they were too lenient.
The trio were then convicted of between six and eight months in jail by Hong Kong's Court of Appeal.
Rights groups criticised the government, saying the appeals were political decisions intended to deter future protests. However, the government denied this, saying there was "absolutely no basis" to claims of political motives.
On Tuesday, Hong Kong's Court of Final Appeal said it had unanimously "quashed the sentences of imprisonment", adding that the jail terms given to the three had been "significantly more severe" than those given for previous cases of unlawful assembly.
However, it also endorsed recent guidelines from the Court of Appeal that outlined stricter sentences for illegal protests, and said "future offenders involved in large-scale unlawful assemblies involving violence" could attract prison sentences.
Wong is currently appealing a separate prison sentence for contempt of court, which is also related to the 2014 protests.
Last week, a group of US lawmakers nominated Wong, Law and Chow for the Nobel Peace Prize, sparking criticism from the Hong Kong and Chinese governments.