A Moscow court convicted four men on Monday, June 3 of kidnapping the son of software empire founder Yevgeny Kaspersky, according to RIA Novosti.

The investigation into the case found Nikolai Savelyev and his son Nikolai, together with Semyon Gromov, Oleg Mayukov and Alexei Ustimchuk, followed the CEO's 20-year-old son Ivan Kaspersky in March 2011, carrying out extensive surveillance to find out his daily schedule.

The suspects grabbed Ivan Kaspersky in the Moscow district of Strogino on April 19, 2011, threw him into their car, and handcuffed and blindfolded him, the Investigative Committee reported.

Then they drove him to an undisclosed location in the Moscow Region, where he was held for a ransom of 3 million euros ($4.3 million). He was freed five days later as a result of a raid by riot police and Federal Security Service officers.

The prosecutor had asked for a seven-year prison sentence for Mayukov, 11 years for Gromov and 12 years each in a high security prison for the Savelyevs. Sentencing will take place at a later date.

Russia’s Kaspersky Lab is a leading developer of anti-virus protection software. Yevgeny Kaspersky, its CEO, was estimated to be the 125th richest man in Russia in 2011 with an $800-million fortune, according to Forbes.