We adopted a scoring system in the curations to evaluate the verified levels and enhance the confidence of immune checkpoint targets. The confidence score is based on the number of publications and sample types (tissues or cell lines) used for experiments. For each target, we calculated the confidence score as follows, Score = N * (C + T), in which N is the number of studies/publications that verified the targets, C and T refer to if the target has been verified in cancer cell lines or patient (or animal) tissues, respectively. Namely, if the target has been verified in cancer cell lines or patient tissues, the C or T value will be set to 1, respectively. Hence, a high score means that the target is more relevant with high confidence. This score could be used for researchers to identify interesting targets with more confidence for research and drug discovery.