Russia's Federal Tax Service recently published guidance letter No. SA-4-7/23972 concerning the application of the country's new general anti-avoidance rule (GAAR) provisions introduced by Federal Law No. 163-FZ of 18 July 2017 ({News-2017-07-28/A/4-previous coverage}). The letter notes that new GAAR provisions may not be applied by the courts in considering cases challenging tax authority dec…