June 7, 2016 (Shareholders Foundation) - An investigation on behalf of investors, who currently hold shares of Rose Rock Midstream LP (NYSE:RRMS), was announced concerning whether the takeover of Rose Rock Midstream LP. by SemGroup Corporation for a value of approximately $24.00 per share is unfair to NYSE:RRMS stockholders.

The investigation by a law firm concerns whether certain officers and directors of Rose Rock Midstream LP breached their fiduciary duties owed to NYSE:RRMS investors in connection with the proposed acquisition.

On May 31, 2016, SemGroup Corporation (NYSE:SEMG) and Rose Rock Midstream LP (NYSE:RRMS) announced an agreement under which SemGroup will acquire all of the outstanding common units of Rose Rock not already owned by SemGroup in an all stock-for-unit transaction at a ratio of 0.8136 SemGroup common shares per Rose Rock common unit, or at a the value of which is equivalent to $24.00 per unit of Rose Rock Midstream LP (NYSE:RRMS).

However, given that at least one analyst has set the high target price for NYSE:RRMS shares at $32.00 per share and given that NYSE:RRMS shares rose to $28.84 per share in the open market on June 7, 2016, the investigation concerns whether the offer is unfair to NYSE:RRMS stockholders. More specifically, the investigation concerns whether the Rose Rock Midstream Board of Directors undertook an adequate sales process, adequately shopped the company before entering into the transaction, maximized shareholder value by negotiating the best price, and acted in the shareholders' best interests in connection with the proposed sale.