Transfer Price Adjustment
There are no objective criteria to describe what "suspicious" is. Only GameMasters are authorized to cancel or adjust abnormal prices, hand out fines to teams or even ban the users involved.
So always report transfers that look suspicious to you by contacting your local GMs.
Good players and money are key aspects of game so a little "Fair Play" is needed. Fair Play in transfers implies that nobody should benefit from abnormal activities on the market. This means that all bids should be in relevance to what could be considered reasonable for the player in question.
You must keep in mind that you may never ever pay an extremely higher amount for a player than his market value. You can always check the market value by using transfer compare.
It's also prohibited to "help" friends or family by buying players at inflated prices. Another form of suspicious transfers are multiple transfers between two teams or transfers between two teams that are 'linked' to each other (e.g. two brothers/sisters on the same ip).
If someone you don't know makes an extremely high bid on one of your players, be smart enough to report it to your local GM. They will find out anyway and you will lose the money that was payed to much anyway, but if you don't report it to your local GM's they could see it as cheating on your part and sanction you about it.
In the past it was allowed to "exchange" players (to make an agreement with another user to make the same extreme high bid on a player of the other person so you could 'exchange' the two players). This is not allowed anymore.