US SB1684

Requires the Secretary of Education to audit at least 30 higher education institutions every 2 years for compliance with foreign gift and contract disclosure requirements under Section 117 of the Higher Education Act, beginning within 60 days of enactment

Prioritizes audits of institutions with the largest endowments (top 1%), those with histories of receiving foreign gifts/contracts, those previously noncompliant, those receiving contributions from foreign entities of concern, and those with formal agreements with federal agencies

Imposes a 300% excise tax on income received by colleges and universities from "foreign countries of concern" (as defined in the Research and Development, Competition, and Innovation Act), applying to institutions with at least 500 tuition-paying students where more than 50% are located in the U.S.

Imposes a 110% excise tax on unreported foreign funding discovered through audits, with tax due within 180 days of audit notification; this tax applies in addition to the 300% tax if funding originated from a foreign country of concern

Requires audit results to be reported to Congress within 30 days of completion and made publicly available on the Department of Education website