The series contains the alphabetically arranged Biographical Dossiers (BD) and forms the largest single file of the Collection, amounting to more than 1,500 names of individuals concerning whom Batchinsky collected materials. This file appears also to have functioned to some extent as Batchinsky's resource collection, from which he extracted materials to build in turn the Choronological and Diary Dossiers and perhaps other files, such as the Subject Dossiers and his Autobiography.
Batchinsky created Biographical Dossiers on people with whom he corresponded or in whom he had a strong interest, assembling a mixture of correspondence (including carbon copies of his own letters), biographical notes (often made by Batchinsky shortly after meeting the individual), photographs, clippings, publications and other material.
A few individuals do not appear in this series as they are subjects of separate sub-collections formed by Batchinsky outside the Biographical Dossiers. In order of appearance, they are: Leonid Bachynsky, Drahomanov, Chyzhevsky, Mexin, Shevchenko, Repnin, Yurkevych, Skoropads'kyi, and Skovoroda Mosendz).