Seems many don't know what OI (open intrest) means, so i will explain it here.
It's very simple actually, but you have to know the difference between OI and what we see on the open long/short on Bitfinex.
Example, we have 4 traders, A,B,C and D. OI is zero at the moment.
A and B want to go long with each 10 contracts
C and D want to go short with each 10 contracts. If they put their orders in A and B will have each 10 long (so 20 total long) and C/D will have each 10 short (20 total. This would mean that the OI goes from zero to 20.
A: 10 long
B: 10 long
C: 10 short
D: 10 short
Now to make things clear how it works i will give another example.
A is bullish and wants to buy 10 more contracts, if C/D sell 10 more than OI would go up to 30.
A: 20 long
B: 10 long
C: 15 short
D: 15 short
But now here it comes, A still wants to buy those 10 more but if B is having doubts with his long position and wants to sell than the OI does NOT change and stays at 20.
A: 20 long
B: 0 long
C: 10 short
D: 10 short
So the higher the OI the more contracts are open in the market, meaning more positions are open to exposure of the movement of the market. This is why we always see big movements when the OI goes up allot, because more people have positions. In other words, more people can loose money again. When you hear me talk about fuel for a long or short squeeze, this is what i mean with this.