<p dir="ltr">Accurate prediction of T cell receptor (TCR) specificity for cognate peptides presented by the major histocompatibility complex (pMHC) is a key challenge in understanding adaptive immunity and enabling immune-based therapeutics and diagnostics. Successful models predicting TCR-pMHC specificity must be able to generalize to novel TCRs and novel pMHCs not observed during model training. Here, we provide a labeled dataset intended for general use as a test of TCR-pMHC model generalization to novel TCRs specific for novel pMHCs.<br></p><p dir="ltr"><br></p><p dir="ltr"><b>Dataset file:</b> "immrep2025_for_release.tsv"</p><p dir="ltr"><b>Detailed dataset description file</b>: "immrep25_dataset_and_methods.pdf"<br></p>