The Securities and Exchange Commission has given the American Stock Exchange the green light to bring in off-floor ETF market makers, a move traders say is necessary for when the Amex merges with the New York Stock Exchange. The so-called Designated Amex Remote Traders (DARTs) will act as automated market makers and will provide continuous quotes, fill trades and bring in new order flow. Until now, most of the options market makers were on the floor. NYSE Arca, which trades all Big Board ETF listings, is completely automated, so it would be difficult to combine Amex’ floor structure with fast-paced trading in the instruments, one trader said. Amex will handle the allocations and set specific performance standards at a later date. It is still unclear how much of the Amex floor would migrate to the Big Board and when. NYSE officials said it was too early in the merger process and no concrete plans have been made yet.