The term “blackout period,” as defined in § 245.100(b), does not include:
(a) A regularly scheduled period in which participants and beneficiaries may not purchase, sell or otherwise acquire or transfer an interest in any equity security of an issuer, if a description of such period, including its frequency and duration and the plan transactions to be suspended or otherwise affected, is:
(1) Incorporated into the individual account plan or included in the documents or instruments under which the plan operates; and
(2) Disclosed to an employee before he or she formally enrolls, or within 30 days following formal enrollment, as a participant under the individual account plan or within 30 days after the adoption of an amendment to the plan. For purposes of this paragraph (a)(2), the disclosure may be provided in any graphic form that is reasonably accessible to the employee; or
(b) Any trading suspension described in § 245.100(b) that is imposed in connection with a corporate merger, acquisition, divestiture or similar transaction involving the plan or plan sponsor, the principal purpose of which is to permit persons affiliated with the acquired or divested entity to become participants or beneficiaries, or to cease to be participants or beneficiaries, in an individual account plan; provided that the persons who become participants or beneficiaries in an individual account plan are not able to participate in the same class of equity securities after the merger, acquisition, divestiture or similar transaction as before the transaction.