US Code - Part I: General rule

Section 501 Exemption from tax on corporations, certain trusts, etc.
Section 502 Feeder organizations
Section 503 Requirements for exemption
Section 504 Status after organization ceases to qualify for exemption under section 501(c)(3) because of substantial lobbying or because of political activities
Section 505 Additional requirements for organizations described in paragraph (9), (17), or (20) of section 501(c)

Exempt organizations

Private foundations