People. Brokers. Firms market makers are hired to keep price down. Period. Been going on forever.. I ran the largest Bond position at one time. If I were going to buy a large amount of bonds I would have all my traders put downside pressure on every quote. I would often sell 50 or 75 million first. And keep pressure on. And then use trusted brokers to buy on the bid side when people would get nervous and sell. Otherwise people would front run me
Pretty sure you are dead wrong. The blocks you see after hours are cumulative buys and sells that have been worked on all day, and what you see is the total.
When one institution trades with another in a dark pool, not sure if anything is reported, semi-instantaneously.
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