Summary List PlacementShares of GlaxoSmithKline rose 6% on Thursday after reports of hedge fund Elliott Management taking a multi-billion pound stake at the British pharmaceutical firm. GSK rose to a high of $38.24, its highest price since January 28. It was last at $38.04 around 10:22 a.m. ET, up around 5.3%. The "significant" investment was confirmed by exclusive sources to the Financial Times Thursday. Elliott, the $42 billion hedge fund known for its activist campaigns, enters the picture at a time when GSK is struggling to overcome a bruised reputation.