National Student Clearinghouse data breach impacts 890 schools. U.S. educational nonprofit National Student Clearinghouse has disclosed a data breach affecting 890 schools using its services across the United States. U.S. educational nonprofit National Student Clearinghouse (NSC) has disclosed a data breach affecting 890 schools using its services across the United States. In a breach notification letter filed with the Office of the California Attorney General, Clearinghouse said that attackers gained access to its MOVEit managed file transfer (MFT) server on May 30 and stole files containing a wide range of personal information. Third-party company: National Student Clearinghouse (NSC).