This article considers one of the key issues in the reception of memoirs, i.e. the contradiction embedded in the specific character of the genre. Lidiya Ginzburg defined it as an interconnection of two counter-directed principles: the mandatory “strife for authenticity” on the one hand, and subjectivity as an “‘inauthenticity’ catalyst” on the other. Being a truthful testimony, a memoir is not a distilled document, purified from different unpremeditated distortions, caused by the incomplete knowledge of the memorialist, their delusions or personal interpretation of stated facts. Agreeing with V. Tyupa’s differentiation between discourse and genre, the author analyses Akhmatova’s reaction to two memoirs and the way scholars treated them and demonstrates the following: 1) a memoir can be regarded as authentic / inauthentic only within a communicative event, i.e. discourse; 2) working with an admittedly inauthentic testimony, Akhmatova applied Lotman’s logic. According to this logic, the key factor in working with a source is neither its authenticity, nor its inauthenticity, but the rightfully stated “correlation between the type of the source and the methodology of its analysis”. In the first case, Akhmatova became a critic of the authors of her biography, who used the book Petersburg Winters by G. Ivanov as a reliable historical source and thus disfigured the corner stone of her creative development. In the second case, she proved that the memoirs of Prince Trubetskoy about the relationship between Pushkin and Aleksandra Goncharova turned from “delirious mumbling” rejected by P. Shchegolev as falsehood into “a document of paramount importance as the only and true story told by d’Anthès himself”.