o Shares of Chesapeake Energy Corporation (NYSE:CHK) and EnCana Corporation (NYSE:ECA) plunged 8.5% and 4.1% respectively following a Reuters report according to which top officials of the firms deliberately avoided bidding against each other

o Old Republic International Corporation (NYSE:ORI) lost 10.1% after it canceled the spinoff of its subsidiary, Republic Financial Indemnity Group

o Shares of Kirby Corporation (NYSE:KEX) fell 11.1%, the highest in the past 20 months after it lowered its earnings forecast for the current quarter as well as for the full year ending December 2012

o Momenta Pharmaceuticals, Inc. (NASDAQ:MNTA) declined 22.4% after a US District Court gave a verdict in favor of rival Teva Pharmaceutical Industries Ltd (NYSE:TEVA). Teva had filed a patent infringement lawsuit for its best-selling multiple sclerosis drug Copaxone against Momenta

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