definiens: means ( a ) if Atlantic has a class of stock ( x ) registered under Section 12(b ) or 12(g ) of the Secu rities Exchange Act of 1934 and that is publicly traded on a major US exchange such as the NYSE or NASDAQ, or ( y ) traded on a major European exchange such as Deutsche Börse or t he London Stock Exchange, such publicly traded common stock of Atlantic, the value of which will be determined [ * * * ] by the average closing price for the 15 trading days immed iately preceding the date the particular milestone event referenced in this Section 6.2 is a chieved ; or ( b ) if Atlantic does not have a class of publicly traded stock, the equity securiti es of Atlantic issued in its most recent venture capital financing occurring prior to the da te the particular milestone event referenced in this Section 6.2 is achieved, which will be issu ed to Isis at the same price per share and with the same rights, preferences and privileges as provided to the other investors in such financing