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Comment by SEJeff | Hacker News Reader

That 100% depends on the exchange actually. Not all exchanges have priority rules like that. It certainly is the case for a lot of futures markets, but definitely not for many places for Equities, Options, or even FX.

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Which major equities exchanges don't do price/time priority?

Can't really say sadly, but it is true. But it is normally the case for Limits, except not all orders are limit orders. You're right mostly, for a certain type of strategy, but not all of them. Ironically I just looked up your profile and on the link you mention Flash Boys: Not So Fast.

I used to work with Peter Kovac, that book's author, at Madison Tyler Technology / EWT LLC (which is now Virtu Financial). He's one of the smartest guys I've ever met and that was a pretty decent book.

Its been awhile since I perused order type documentation so anything is possible, but I don't ever remember seeing an order type that can jump a resting limit order from the past on any any exchange I've looked at.

I have seen odd priority rules around how orders get around sweep or self match protections and the like, but not jumping a resting, visible order.

Given the order type doco is public for SEC regulated exchanges I doubt your IP agreement restricts you from slipping me a link right? ;)

ISO limits that create a new price are usually given better priority than Hide-not-slide orders entered with the equivalent working price, even if they were accepted before the ISO limit. Depends on the exchange obviously.

Sure and the non-visible parts of icebergs end up getting later priority than new limits at the same level. I'm not arguing that there aren't order types you can do that will put you at the back of the line priority wise, I'm suggesting the alternative.

If I put a vanilla limit at a level and don't cancel it (and its GTC) today, I've never seen an order type that would allow someone to jump me in the priority queue tomorrow.

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