MSCI Inc., (MXB) – $32.61 +$4.02 – The shares rallied 14.06% after the company announced that it was acquiring RiskMetrics Group (RISK) for approximately $1.5 billion. MSCI Inc., provides investment decision support tools to investment institutions.

Terra Industries (TRA) -$45.67 +$4.47 – CF Industries (CF) announced an offer to acquire the fertilizer producer for $37.15 in cash and 0.0953 of a share of CF Industries common stock for each Terra Industries share, for a total of $47.40 per share or $4.74 billion. This trumps a $4.1 billion offer by Norwegian company Yara, that was made last month, which Terra agreed to.

This is a long running saga, with Terra Industries having rejected several offers from CF over the past year, apparently not wanting to sell out to a competitor. CF had withdrawn its last offer as it had come to the conclusion that Terra was absolutely not for sale. They made this recent offer, since Terra is now obviously amendable to a sale.

In its letter to Terra’s board, CF stated the following: As you are aware, we were advised that no information would be provided to us because “Terra is not for sale.” Following this response, we withdrew our offer, and we have not had any further communication with you. We do not understand how Terra could have entered into an agreement with Yara without giving CF Industries an opportunity to bid on a level playing field. We also do not understand how Terra could have accepted an offer from Yara with a risk adjusted present value that we believe was not higher than the offer CF Industries had made in December 2009.”