Mr. Durov launched Telegram in late 2013 with his brother, Nikolai, just months before he was pushed out of VK, the Russian social-media platform he founded. Mr. Durov pitched his new app—funded with the proceeds from the VK sale—less as a business than as a way for people to send messages while avoiding government surveillance and censorship.
A Telegram spokesman declined to comment on the bond issue or the amount of the debt the company has due. The spokesman said Telegram’s equipment and bandwidth costs are growing because it has consistently posted more than 40% year-to-year growth in users.
