Definition of Service Recipient Stock

[SycamoreFan]

Does anyone have some insight into what to what is meant by the following language in 1.409A-1(b)(5)(iii)(A): "Except as otherwise provided in paragraphs (b)(5)(iii)(B), ©, and (D) of this section, the term service recipient stock means a class of stock that, as of the date of grant, is common stock for purposes of section 305 and the regulations thereunder of a corporation that is an eligible issuer of service recipient stock (as defined in paragraph (b)(5)(iii)(E) of this section). Unless I'm missing something, I can't find anything in Section 305 or the regulations thereunder that helps define common stock.