This is an industry problem, not a broker problem. I have several times been hit with "swap corrections", from several brokers, so this issue is not limited to ICM. Broker T & C allow for them to correct the swaps retroactively when there has been a manifest error.
The problem with this argument is the same as a broker just saying that your trade has been cancelled because it didn't "follow the rules".
This is way too arbitrary, and can easily be abused.
You are correct that there isn't an industry standard for the swap rate itself. But there are still principles of fair dealing....mainly that the trade is finalized once the position is opened (initially) and then again when offset (closed, partially and/or eventually in full). What ICM and other brokers are doing is still an
asymmetrical reneging.
In short, it's very
bucketshop
-y type of behavior.
There is nothing transparent about the swaps. They come from the liquidity providers and brokers actually have little say in the matter, other than any padding that they might take.
It is posted in the trading platform what the current rate being charged here. And the broker has full control over what is streamed to the trading platform. To say the broker has little say in the matter implies that they don't have any responsibility to ensure the rates or prices are correct.
Even if we give ICM the benefit of the doubt (that there was a "real" error in swap rate),
nearly 10 weeks went by and the broker didn't notice something peculiar? If the rates originally come from the LPs, then where is this adjustment coming from 9+ weeks in?
I really couldn't see any agency model brokerage doing this. Because the rates given to them from LP/prime broker are streamed to them. They add whatever markup and then that's the rate displayed on the platform. The swap rates are refreshed at least once a day at rollover and can be adjusted during the day.
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@compu-forex have you ever received any
positive adjustment from these "swap corrections" you were hit with in the past (from any broker, not necessarily ICM?
How many times did you get a
positive adjustment swap (missed profit was added to your account) vs a
negative adjustment swap (they jacked your account balance for more)?