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50 U.S. Code Chapter 36 - FOREIGN INTELLIGENCE SURVEILLANCE

SUBCHAPTER I—ELECTRONIC SURVEILLANCE (§§ 1801 – 1813)
SUBCHAPTER II—PHYSICAL SEARCHES (§§ 1821 – 1829)
SUBCHAPTER III—PEN REGISTERS AND TRAP AND TRACE DEVICES FOR FOREIGN INTELLIGENCE PURPOSES (§§ 1841 – 1846)
SUBCHAPTER IV—ACCESS TO CERTAIN BUSINESS RECORDS FOR FOREIGN INTELLIGENCE PURPOSES (§§ 1861 – 1864)
SUBCHAPTER V—OVERSIGHT (§§ 1871 – 1874)
SUBCHAPTER VI—ADDITIONAL PROCEDURES REGARDING CERTAIN PERSONS OUTSIDE THE UNITED STATES (§§ 1881 – 1881g)
SUBCHAPTER VII—PROTECTION OF PERSONS ASSISTING THE GOVERNMENT (§§ 1885 – 1885c)