FOIA exemptions

Overview
The U.S. Freedom of Information Act of 1974 contains certain exemptions from disclosure:

law
 * Exemption 1: classified national defense and foreign relations information
 * Exemption 2: internal agency rules and practices (personnel)
 * Exemption 3: information that is prohibited from disclosure by another federal
 * Exemption 4: trade secrets and other confidential business information
 * Exemption 5: inter-agency or intra-agency communications that are protected by legal privileges.
 * Exemption 6: information involving matters of personal privacy
 * Exemption 7: records or information compiled for law enforcement purposes, to the extent that the production of those records A) could reasonably be expected to interfere with enforcement proceedings, B) would deprive a person of a right to a fair trial or an impartial adjudication, C) could reasonably be expected to constitute an unwarranted invasion of personal privacy, D) could reasonably be expected to disclose the identity of a confidential source, E) would disclose techniques and procedures for law enforcement investigations or prosecutions, or would disclose guidelines for law enforcement investigations or procedures, or F) could reasonably be expected to endanger the life or physical safety of any individual.
 * Exemption 8: information relating to the supervision of financial institutions
 * Exemption 9: geological information on wells