 Citigroup Inc. trimmed its stake in Altus Midstream NYSE:ALTM by 6.2 in the first quarter, according to its most recent Form 13F filing with the Securities and Exchange Commission. The firm owned 900,999 shares of the companys stock after selling 59,691 shares during the quarter. Citigroup Inc. owned about 0.28 of Altus Midstream worth 676,000 ... 