17 CFR § 230.145
Rule 145 ( 230.145 of this chapter) is designed to make available the protection provided by registration under the Securities Act of 1933, as amended (Act), to persons who are offered securities in a business combination of the type described in paragraphs (a) (1), (2) and (3) of the rule. The thrust of the rule is that an offer, offer to sell, offer for sale, or sale occurs when there is submitted to security holders a plan or agreement pursuant to which such holders are required to elect, on the basis of what is in substance a new investment decision, whether to accept a new or different security in exchange for their existing security. Rule 145 embodies the Commission's determination that such transactions are subject to the registration requirements of the Act, and that the previously existing no-sale theory of Rule 133 is no longer consistent with the statutory purposes of the Act. See Release No. 33-5316 (October 6, 1972) [37 FR 23631]. Securities issued in transactions described in paragraph (a) of Rule 145 may be registered on Form S-4 or F-4 ( 239.25 or 239.34 of this chapter) or Form N-14 ( 239.23 of this chapter) under the Act.