The article comments on the Ruling of the Plenum of the Supreme Court of Russia on the challenging of cadastral value. The aim of the comment is to reveal the general conceptual basis of the Ruling that determines approach to distinct legal problems. The analysis of different issues resolved in the Ruling (including, inter alia, persons entitled to challenge the cadastral value, time limits for bringing such claims, retrospective effect of its adjustment, remedies available to claimants) leads to the conclusion that the Supreme Court considers the cadastral value as the base for taxation, despite the fact that the cadastral value has many other applications. This conclusion reveals the foundation of the Supreme Court's interpretation and provides tools for resolution of other problems that are not covered by the Ruling.