Verus International Inc (VRUS)

[Nestegg McMuffin]

Schnozzberry, here's a couple of explanations.

1) A MM is sitting on an all-or-nothing order (sell or buy) which does not go up in the front window so to speak, so you can't see it on the bid or ask, even if the price is between the current spread. Your bid could get filled below the ask if the MM accumulates enough smaller orders to fill that all-or-nothing order.

2) An MM is executing a "no hold' order. This is where you hand over all control to the MM to decide how and when to sell or buy your order. For example, you want to buy 5million shares below .021 but you don't want to put that up as one bid and drive the price up. The MM will purchase those shares below radar for you over several days if needed.
If you order is big enough, it will be worth a MM walking down the price to see if they can generate bids to fill the whole order.
Likewise, a big long selling off some of their position or a company diluting say 10 million new shares to pay a note will do a no hold order so the MM will 'discreetly' sell off shares without tanking the price too obviously.

Any refinements to these explanations most welcome.