When the ask increases and is being met w/ buying, CINN is stepping in front of the best ask in order to keep the pps from rising further. Capping the action and causing people to sell when they see the pps stall thus killing momo. As it's been pointed out, you need a large inventory of shares to do this or you are shorting like crazy.
“A fool and his money are soon parted.” ~Thomas Tusser
Market Data 
Markets 
AI
