taffy, here's the gist of the theory. If a buyer wants to...

taffy, here's the gist of the theory. If a buyer wants to accumulate a lot of shares in a company, they will seek to do so at 'low' prices (for obvious reasons). So the theory is that when their buying (and buying by other parties) pushes the price up too far for their liking, they will temporarily stop buying and perhaps even sell some shares in the hope that this will result in the price dropping back down to a level where they are comfortable to start accumulating again. This is 'capping'. It's a delicate operation, particularly selling shares when your primary goal is to accumulate.