American Shared Hospital Services (NYSEMKT:AMS) Director Raymond C. Stachowiak bought 400,000 shares of American Shared Hospital Services stock in a transaction that occurred on Thursday, June 12th. The shares were purchased at an average cost of $2.43 per share, with a total value of $972,000.00. Following the purchase, the director now directly owns 30,347 shares of the company’s stock, valued at approximately $73,743. American Shared Hospital Services (NYSEMKT:AMS) stock performance was 12.89% in last session and finished the day at $2.84. Traded volume was 89.02K shares in the last session and the average volume of the stock remained 12.21K shares. The beta of the stock remained 0.65. American Shared Hospital Services (NYSEMKT:AMS) insider ownership is 17.30%.

USA-based Portola Pharmaceuticals (NASDAQ:PTLA) has entered into a second clinical collaboration agreement with Japanese drug major Daiichi Sankyo (TYO: 4568) to study andexanet alfa, Portola’s investigational Factor Xa inhibitor antidote, in Phase III registration studies with Daiichi Sankyo’s Factor Xa inhibitor edoxaban (proposed trade name Savaysa). Portola Pharmaceuticals Inc (NASDAQ:PTLA) rose 0.70 percent to $25.80 Friday on volume of 209.07K shares. The intra-day range of the stock was $25.28 to $26.09. Portola Pharmaceuticals Inc (NASDAQ:PTLA) has a market capitalization of $1.06billion.

Zacks upgraded shares of Mercury General Corp. (NYSE:MCY) from a neutral rating to an outperform rating in a research report released. Zacks currently has $50.80 price objective on the stock. Mercury General Corporation (NYSE:MCY)’s stock on July 11, 2014 reported a increase of 0.86% to the closing price of $47.00. Its fifty two weeks range is $40.60 -$49.05. The total market capitalization recorded $2.58billion. The overall volume in the last trading session was 105.03K shares. In its share capital, MCY has 54.98million outstanding shares.

Rose Rock Midstream®, LP and SemGroup Corp (NYSE:SEMG) have announced today that Rose Rock has acquired from SemGroup Corp (NYSE:SEMG) the remaining one-third interest in SemCrude Pipeline, LLC, which owns a 51% interest in White Cliffs Pipeline LLC for US$ 300 million. Rose Rock now owns a 100% interest in SemCrude Pipeline and indirectly owns a 51% interest in White Cliffs Pipeline. On Friday, shares of SemGroup Corp (NYSE:SEMG) advanced 0.13% to close the day at $78.65. Company return on investment (ROI) is 8.10% and its monthly performance is recorded as 15.51%.  SemGroup Corp (NYSE:SEMG) quarterly revenue growth is 21.26%.