jefferies analyst ken usdin reiterated a buy rating on state street corp on wednesday and said the retention of 15 of blackrock incs blk etf servicing business will benefit the company state street revealed in filings earlier this year that it would lose a chunk of its etf servicing business from blackrock blackrock has now finalized its new structure with citigroup inc c handling 40 of the 23 trillion etf business jpmorgan chase  co jpm handling 30 also bank of new york mellon corp bk and state street with 15 each we see this as a win for everyone with the loss welltelegraphed for stt but the retention of 15 a positive as are the new wins for the others in a fastgrowing asset class usdin said usdin said jefferies has already subtracted 150 million in revenue from its models but the actual figure could be about 160 million given asset value growth shares of state street fell 09 in morning trading