§ 930. Possession of firearms and dangerous weapons in Federal facilities
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(a) Except as provided in subsection (d), whoever knowingly possesses or causes to be present a firearm or other dangerous weapon in a Federal facility (other than a Federal court facility), or attempts to do so, shall be fined under this title or imprisoned not more than 1 year, or both.
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(d) Subsection (a) shall not apply to—
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(3) the lawful carrying of firearms or other dangerous weapons in a Federal facility incident to hunting
or other lawful purposes.
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(g) As used in this section:
(1) The term “Federal facility” means a building or part thereof owned or leased by the Federal Government, where Federal employees are regularly present for the purpose of performing their official duties.
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(h) Notice of the provisions of subsections (a) and (b)
shall be posted conspicuously at each public entrance to each Federal facility, and notice of subsection (e) shall be posted conspicuously at each public entrance to each Federal court facility, and no person shall be convicted of an offense under subsection (a) or (e) with respect to a Federal facility if such notice is not so posted at such facility, unless such person had actual notice of subsection (a) or (e), as the case may be.