Quote from: Lisieux on July 24, 2017, 10:09:36 AM

Margin Account compromised due a BUG in their systems. I'm not the first person whos got this bug. $40.000 dissappeared when I closed a short position.

https://www.reddit.com/r/CryptoCurrency/comments/6p0gzh/help_me_to_contact_poloniex_margin_bug_40000/

Well, polo margin system lead self a bit strange from first view if you have multiple opened short positions, as i understand from this post you had at least eth and fct? I argued with them a lot about it while their support still worked, since i as well couldn't understand why after closing short potion btc sometimes doasn't appear on balance.

If you have multiple opened shorts let's say:

POSITIONS:
DASH Short -100 +2 BTC
LTC Short -1000 +4 BTC
ETH Short -100 +1 BTC

Your

MARGIN ACCOUNT on right of the page shows something like that:
Total Margin Value   20 BTC
Unrealized P/L   7 BTC
Unrealized Lending Fees   -0.00596374 BTC

You close let's say ltc short potion and await that
your total amount of btc increase on at least 4 btc or little less if count fee + fact that you buy for higher price you expected.

But suddenly (no clue why it sometimes works so) you may see that margin account didn't change

POSITIONS:
DASH Short -100 +2 BTC
ETH Short -100 +1 BTC

Your
MARGIN ACCOUNT shows:
Total Margin Value   20 BTC
Unrealized P/L   7 BTC

instead of
Total Margin Value   24 BTC
Unrealized P/L   3 BTC

mean this 4 btc somehow goes to total Unrealized P/L and you will get your 4 btc only after ALL short positions will be closed.

Problem that if you often opened and closed shorts but never fully closed all of them, diffrence between total unrealized P/L you currently have and unrealized P/L you think should be may be big, if you didn't pay attention on this before. You may just didn't notice this diffrence before and after closing all shorts you may see that you got less or more btc that you thought.

Not sure that it is this case but for my long history of margin trade on polo i meet only with this sort of "bug". Well if not count negative "Base Price" but it is a bit another case...