Example. Corporation M has outstanding 100 shares of common stock which are owned as follows: B, 75 shares, C, son of B, 20 shares, and D, daughter of B, 5 shares. Corporation M owns the stock of Corporation X. B sells his 75 shares of Corporation M stock to Corporation X. Under section 302(b)(3) this is a termination of B's entire interest in Corporation M and the full amount received from the sale of his stock will be treated as payment in exchange for this stock, provided he fulfills the requirements of section 302(c)(2) (relating to an acquisition of an interest in the corporations).
26 C.F.R. §1.304-3