Over time MNTA's cash build will start to overwhelm and investors will take notice
Momenta's shareholders will only see reasonable gains once Momenta moves some other products forward. Momenta's cash, earnings or balance sheet mean nothing to the normal shareholder unless at some point they issue div's or something of the sort.
Momenta needs to produce a future, and with M118 basically on life support the only thing they have publically is a M402, a preclinical compound.