Quote of 50 USC § 3033 (k)(5)(G), the specific provision cited within the IC "Whistleblower" Complaint at page 1.
2016 US Code Title 50 - War and National Defense Chapter 44 - National Security Subchapter I - Coordination for National Security Sec. 3033 - Inspector General of the Intelligence Community
50 U.S.C. § 3033 (2016)
§3033. Inspector General of the Intelligence Community
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(k) Reports
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(5) (A) An employee of an element of the intelligence community, an employee assigned or detailed to an element of the intelligence community, or an employee of a contractor to the intelligence community who intends to report to Congress a complaint or information with respect to an urgent concern may report such complaint or information to the Inspector General.
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(G)In this paragraph, the term urgent concern'' means any of the following:
(i) A serious or flagrant problem, abuse, violation of law or Executive order, or deficiency relating to the funding, administration, or operation of an intelligence activity within the responsibility and authority of the Director of National Intelligence involving classified information, but does not include differences of opinions concerning public policy matters.
(ii) A false statement to Congress, or a willful withholding from Congress, on an issue of material fact relating to the funding, administration, or operation of an intelligence activity.
(iii) An action, including a personnel action described in section 2302(a)(2)(A) of title 5, constituting reprisal or threat of reprisal prohibited under subsection (g)(3)(B) of this section in response to an employee's reporting an urgent concern in accordance with this paragraph.