Interesting point: stocks are not allowed to be quoted beyond 4 decimal points, but can still be traded beyond 4 decimal points.
Here's how I think it works: a MM buys a whack of shares for a lump sum, say 100 million shares for $5,000. Worked out proportionately, that's technically .00005/share. He then dumps the whole load to several different buyers for $7,000. Although no one ever mentions the fifth decimal point, it works out to .00007/share when the division is done.
See what I mean? No one put in an order for X amount of shares at .00007, they just put in an order for the best price they could get. Does this make sense?
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