Diversity and Inclusion Transparency in the Defense Industrial Base Act This bill provides that the Department of Defense (DOD) must require each contractor who is awarded a major contract to submit a report on diversity and inclusion by the last day of each full fiscal year during the period of the contract. In relation to a major defense acquisition program, a major contract means each of the six largest prime, associate, or government-furnished equipment contracts that is in excess of $40 million and that is not a firm, fixed-price contract. DOD must annually submit to Congress a report summarizing the diversity and inclusion reports. Such reports must be made publicly available on a DOD website.