Prosecutors are acting on a request by State Duma deputy from the ruling United Russia party Robert Shlegel, according to a copy of the prosecutor's request posted by Dozhd head Natalya Sindeyeva on Twitter.
Shlegel said in messages on Twitter that he had filed a request with prosecutors in December, asking them to check whether Dozhd had served as a sponsor and organizer of opposition rallies at Bolotnaya Ploshchad and Prospekt Akademika Sakharova.
"Dozhd, in my view, acted as an 'information sponsor' and partly as an organizer of these events," the Duma deputy wrote.
"The question arose whether this is simple interest or whether it has a financial motive underneath it," he wrote.
In addition to information regarding Dozhd's coverage of the rallies, prosecutors also requested tax documents and a copy of the channel's editorial charter.
Earlier this week, radio station Ekho Moskvy announced that its owner, Gazprom-Media, had demanded a reshuffling of the station's board of directors, prompting fresh fears of censorship by authorities.