could be... could be.
With a regular stock I think usually they just short you whatever shares and in some cases, if they want to squash the pps down aggressively for whatever reasons, they just sluff off concerns figuring thay can satify the locate requirement eventually by finding one of thier buddies with a pile of warrants or convertibles. But with mosh, there are none. and, the float size is fixed - can't be increased...
usually the restriction thing is something else - they won't say exactly, but it could be dwindling pool as well, i guess.
