Prosecutors were seeking a nine-year sentence for Yashin, a Moscow district councillor. Sentencing was due later in the day.
Yashin was tried over a YouTube video released in April in which he discussed evidence uncovered by Western journalists of Russian war crimes in Bucha, near Kyiv, and cast doubt on the official Moscow version that such reports had been fabricated as a "provocation" against Russia.
Russia passed new legislation after invading Ukraine on Feb. 24 that provides for jail terms of up to 15 years for disseminating false information about the military.
In his final statement to the court this week, Yashin appealed directly to President Vladimir Putin, describing him as "the person responsible for this slaughter" and asking him to "stop this madness".
(Reporting by Reuters; Writing by Mark Trevelyan and Jake Cordell; Editing by Kevin Liffey)
