Dr. Aleksey Zalesov, Managing Partner of «A.Zalesov & Partners» Patent & Law Firm, has contributed to the Forth Issue of the Russian specialized IP magazine «The Patent Attorney» with his article «Validity Of A Patent With Wrong Priority Claiming in Russia» (in Russian). Neither Russian, nor Eurasian Patent Law does not stipulate any legal consequences for wrong indication of priority: neither sanctions for intentional wrong indication, nor possibility to correct this error, which leads to the fact that patents issued with such defects are difficult to challenge by third parties in some cases leads to ungrounded broadened patent rights in view of prior art. Due to this lacuna in the law, even in case Rospatent or the court afterwards considering patent validity agree, that the priority was wrongly claimed, does not have possibility to heal this omission of the expertise and to set up the right priority, or to include a prior art reference in the interval between the date of filing and the date of convention priority into consideration of the patent validity. The article discusses different possibilities of healing this lacuna in the law.