17 CFR § 240.12d2-1 - Suspension of trading.
(a) A national securities exchange may suspend from trading a security listed and registered thereon in accordance with its rules. Such exchange shall promptly notify the Commission of any such suspension, the effective date thereof, and the reasons therefor.
(b) Any such suspension may be continued until such time as it shall appear to the Commission that such suspension is designed to evade the provisions of section 12(d) and the rules and regulations thereunder relating to the withdrawal and striking of a security from listing and registration. During the continuance of such suspension the exchange shall notify the Commission promptly of any change in the reasons for the suspension. Upon the restoration to trading of any security suspended under this rule, the exchange shall notify the Commission promptly of the effective date thereof.
(c) Suspension of trading shall not terminate the registration of any security.