On April 19, 2012, GlaxoSmithKline (GSK) made a takeover bid for HGS, offering $13.00 per share for a total valuation of $2.59 billion. The HGS board "...in consultation with independent financial and legal advisors, has carefully reviewed and considered the GSK offer and has determined that the offer does not reflect the value inherent in HGS." Glaxo then tried to buy HGS shares on the open market, but the HGS board of directors adopted a "poison pill" shareholder rights plan that led Glaxo to back off. Shareholders sued the HGS board for adopting the plan. On July 16, 2012, HGS agreed to be purchased by GSK for $3.6 billion.