DISCLAIMER You are free to use VDJdb in research studies for the purpose of RepSeq sample and T-cell clonotype list annotation. However, the authors request priority in publishing a meta-analysis of the dataset aggregated and stored here. This message will be removed once VDJdb is officially published in a peer-review journal. The primary goal of VDJdb is to facilitate access to existing information on T-cell receptor antigen specificities, i.e. the ability to recognize certain epitopes in certain MHC contexts. Our mission is to both aggregate the scarce TCR specificity information available so far and to create a curated repository to store such data. In addition to routine database updates providing the most up-to-date information, we make our best to ensure data consistency and fight irregularities in TCR specificity reporting with a complex database validation scheme: We take into account all available information on experimental setup used to identify antigen-specific TCR sequences and assign a single confidence score to highligh most reliable records at the database generation stage. Each database record is also automatically checked against a database of V/J segment germline sequences to ensure standardized and consistent reporting of V-J junctions and CDR3 sequences that define T-cell clones.