There have been anomalies in at least the ETH-BTC & ETC-ETH markets. For a description see the quote:
NEW warning to Kraken users. Kraken is knowingly presenting false trade data in their ledgers.
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In this particular case, on January 29 2018, around 12 o 'clock CET the price in ETH-BTC the market did a massive drop from 0.10475 down to below 0.09525 ETH/BTC. Our friend had several open positions in that range (all of them opened before 12 o 'clock on the 29th). However none of the positions were traded in this drop even though their limit was clearly passed. Please take a look at the linked screenshot.
https://www.dropbox.com/s/5x3kt58t4ch8x2i/20180129_1200CET_Spike_ETHBTC.png?dl=0Since the orders were not closed, he contacted the Kraken support in order to have them fill the orders according to Krake's own ToS as their price limit was passed.
But as expected Kraken is denying to fill these positions. At first, the support tried to push it on the FIFO principle and that orders do not have to be traded when their limit is reached, since other folk could have placed orders their before. However, it was restated that not only the price was reached, but that the price was clearly passed, and therefore the orders should have been traded.
Kraken then switched their argument. Now, Kraken replied to our friend, that it is possible that false data is being presented in the OHLC-history. Furthermore, Kraken states that no trades actually took place during this drop. The problem for Kraken here is that our friend seems to have proof that there was at least one trade which took place during this drop. (This just causes us to repeat one thing again.
The people at Kraken are liars and frauds, and should be locked up ASAP)
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We drew our conclusions some time ago, we can only warn people who are still trading on this SCAM exchange
If you have encountered similar damage by Kraken and are being denied compensation, then we strongly advise to take screenshots and other means of documenting the case. Then contact relevant authorities (preferably USA) and report the case to them.
It should be noted that these issues have persisted through the update, and have been encountered since at least spring 2017