When the only offers to buy the stock come at the bid, they have no choice but to undercut the ask. Wash, rinse, repeat. It's like magic, eh?
currently known one long's buy @ bid .. tho' input (paraphrasing here) was that the bid was @ 035 (NITE) .. but time stamp shows UC on ask by CDEL for the *trade* something many of us have seen b4 .. legit bid becomes the UC ask .. so the next round of *shorting* down can transpire by NR ..