alt Hacker News> My order on Tesla doesn't affect your order on Apple
not necessarily
many exchanges allow orders into one instrument to match on another
(very, very common on derivatives exchanges)
Replies
halfmatthalfcat • yesterday at 4:43 PM
The amount of multi-leg strategies is insane
Yes, I was going to note that this doesn't necessarily apply on derivatives exchanges. But
a) I don't know of any exchange where this could be true for specifically Apple and Tesla, so the example is OK
b) you can still get some level of isolation, even on commodities exchanges you can't typically affect the gold book with your crude oil order (the typical case is that your order to buy oil futures in 2027 matches against someone selling oil in 2026, plus someone selling a calendar spread)
c) for exchanges that do offer this kind of functionality, one of the ways they deal with high volumes is by temporarily disabling this feature.