Round Rock Advisors LLC lowered its position in SPDR S&P Biotech ETF (NYSEARCA:XBI – Free Report) by 2.6% during the first quarter, Holdings Channel.com reports. The fund owned 6,841 shares of the exchange traded fund’s stock after selling 184 shares during the quarter. Round Rock Advisors LLC’s holdings in SPDR S&P Biotech ETF were worth […]