Ticker Talk

Knight/Trimark Group Inc., the biggest Nasdaq market maker, said Thursday that it will clear and settle all its securities transactions through Merrill Lynch & Co. instead of PaineWebber Inc. Jersey City, N.J.-based Knight said it will give its business to Merrill’s Broadcort Capital Corp. starting in mid-October. Knight, a 4-year-old company, had been using PaineWebber Group’s Correspondent Services Corp. The agreement ties Merrill, the biggest brokerage and a new entrant in Internet stock trading, to Knight, which has seen its trades more than double in the last year, driven by growth in online trading. Knight shares surged $6 to $40. Merrill rose $1.13 to $79.63, and PaineWebber fell 75 cents to $42.19. . . . San Francisco-based Andromedia Inc., which develops Internet marketing software, announced plans for an IPO that could raise as much as $40 million.