As of March 2013, the U.S. Dept. of Health and Human Services (HHS) has investigated over 19,306 cases that have been resolved by requiring changes in privacy practice or by corrective action. If noncompliance is determined by HHS, entities must apply corrective measures. Complaints have been investigated against many different types of businesses such as national pharmacy chains, major health care centers, insurance groups, hospital chains and other small providers. There were 9,146 cases where the HHS investigation found that HIPAA was followed correctly. There were 44,118 cases that HHS did not find eligible cause for enforcement; for example, a violation that started before HIPAA started; cases withdrawn by the pursuer; or an activity that does not actually violate the Rules. According to the HHS website, the following lists the issues that have been reported according to frequency: