MNTA – Momenta Pharmaceuticals, Inc. – Shares of the biotechnology company spent the better part of the trading session on the decline, falling as much as 3.5% in afternoon trading to an intraday low of $14.38. The stock had more than doubled toward the end of July, rallying 122.6% from $11.77 up to $26.20 in a matter of two trading sessions, but those gains proved to be short-lived. MNTA’s shares spent the final week of July and the month of August in a downward spiral, slipping 46.2% from its 52-week high of $26.20 on July 26, 2010, down to a low of $14.10 on August 31, 2010. One options investor observed today does not seem to think Momenta’s shares have as yet bottomed out. The pessimistic player initiated a ratio put spread to position for the price of the underlying stock to extend losses through expiration in January 2011. The trader purchased 4,000 puts at the January 2011 $12.5 strike at a premium of $2.25 each, and sold 8,000 puts at the lower January 2011 $10 strike for premium of $1.00 apiece. Net premium paid to establish the transaction is reduced to just $0.25 per contract. The investor is prepared to make money should MNTA shares plunge 14.8% from today’s low of $14.38 to breach the effective breakeven price of $12.25 by expiration day. Maximum potential profits of $2.25 per contract are available to the ratio-spreader if shares fall 30.45% to settle at $10.00 at expiration. MNTA’s shares last traded at a 52-week low of $8.70 back on November 3, 2009.