The financial regulator is investigating the possibility of inside trading, but a closer examination of the charts gives us a better idea of what happened.
The AUD/USD chart (on the left) looks like a clear case of informed trading given high volume and a large price move in the minute before the RBA's official policy decision. But there's a problem: the AUD/JPY chart (on the right) moves exactly the same way at the same time.
On the one-minute charts used here the RBA's decision was at 14:00. On every AUD pair one-minute chart the market moves dramatically at 13:59 – the minute before the RBA decision.
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The Oanda five-second chart shows the move started at 13:59:50 on every AUD pair. By 14:00 all that was left was for the market to digest what had already happened and price activity moved sideways.
The exact replication of the fast up-move in all AUD pairs in the 10 seconds prior to the official RBA decision is not a sign of inside trading. It's more reasonably explained by the early loading of RBA information on their website before the data is officially released. What the charts show is global market reacting to information as it becomes available to all market participants.
The charts clearly show that the RBA's decision became available to many participants in the minute prior to the official release. These moves are captured across all pairs by High Frequency Quantitative Trading Algorithms perhaps running in the Dark Pools.
It appears the problem is in the way the RBA loads this data to its website in preparation for its official release. The duplication of behaviour across all AUD pairs shows this information is available to many, if not all, participants at the same time.
For inside trading to be present there would have to be a significant move prior to 14:00 andprior to the broad market move at 13:59. This did not happen.
The FX market is the deepest and most liquid market in the world. It would be a courageous – and foolish – inside trader who repeated this activity in February, March and again in April, knowing that the regulator was closely watching. The charts always tell the true story.