** GlobalFoundries GFS.O shares down 5% after hours at $41.88 as its majority owner plans to reduce its stake in the chipmaker

** Abu Dhabi sovereign wealth fund Mubadala Investment Company offering 20 mln shares, per the prospectus

** GFS intends to repurchase $300 mln of the offering shares

** JP Morgan and Morgan Stanley joint bookrunners

** Prior to offering, Mubadala held ~450.5 mln shares, or ~81% of co's ~556.4 mln shares outstanding

** GFS stock on Weds fell 5.4% to close at $44.09, reducing YTD gain to 26%

** One of the few large foundries with significant capacity outside China and Taiwan, GFS runs chip plants in Germany, Singapore, New York and Vermont

** Of 22 analysts covering the stock, recommendation breakdown is 10 "strong buy" or "buy", 11 "hold" and 1 "sell"; median PT $50, per LSEG

(Lance Tupper is a Reuters market analyst. The views expressed are his own)

((lance.tupper@tr.com 1-646-279-6380))