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> What new information?

Stuff that happens in the real world. The stuff that all security prices are eventually based on. It's not a closed system you know?

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Ah, that's why I wanted an example. Your answer is fairly obvious, but it's pretty absolute too so there's no way to ask questions like "is this information actually going to affect the bid size or price of a bidder?" or "is this event important but infrequent, like quarterly reporting?"

For example, infrequent important events will result in a race for people to submit at the last microsecond, but because they're infrequent 99% of the time the 10ms buffering will effectively change the behaviour of market participants.

At the level of a penny, which is what the minimum price change is on most US stocks, almost anything can affect a sophisticated market-maker or proprietary trader's pricing: information in the stock's own order book, the price of related securities globally like the same stock trading in foreign markets, prices of correlated stocks, index futures prices around the world, his or her risk exposure in that stock and others in a portfolio, foreign exchange and interest rate market shifts, news feeds, sentiment analysis of online sources like twitter, company exposure to oil or other commodity price changes, etc. etc.

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