The move is the latest publicity-grabbing headline to come just two months before the Sochi Games. First, Russian oligarch Mikhail Khodorkovsky was released after a decade in prison, and then the last two Pussy Riot activists were pardoned and freed.
Greenpeace International spokesman Aaron Gray-Block said he hoped the environmental activists could be free for Christmas.
"They will be free to leave Russia once they get the right stamps in their passports from the migration service," he said.
The 30 crew members aboard a Greenpeace ship were detained at a Russian oil rig in September and were held for two months before they were released last month.
Also Read
Several more of the Greenpeace activists are expected to receive similar amnesty notifications.
The crew members were originally accused of piracy, a charge that was later changed to hooliganism.
It was unclear when the activist, who was not named, would be free to leave Russia.