17 CFR 230.145a: a Business combinations with reporting shell companies.

With respect to a reporting shell company's shareholders, any direct or indirect business combination of a reporting shell company that is not a business combination related shell company involving another entity that is not a shell company, as those terms are defined in § 230.405, is deemed to involve an offer, offer to sell, offer for sale, or sale within the meaning of section 2(a)(3) of the Act. For purposes of this section, a reporting shell company is a company other than an asset-backed issuer as defined in § 229.1101(b) of this chapter (Item 1101(b) of Regulation AB), that has:

(a) No or nominal operations;

(b) Either:

(1) No or nominal assets;

(2) Assets consisting solely of cash and cash equivalents; or

(3) Assets consisting of any amount of cash and cash equivalents and nominal other assets; and

(c) An obligation to file reports under section 13 (15 U.S.C. 78m) or section 15(d) (15 U.S.C. 78o(d)) of the Securities Exchange Act of 1934 (15 U.S.C. 78a et seq.).