Account holders whose data is sent to the IRS under FATCA should have the right to know what data has been sent. This has been addressed in several blog posts:
As discussed in these posts, domestic US taxpayers whose data is reported to the IRS are entitled to a form 1099 informing them of the data that has been reported. This allows taxpayers to amend erroneous data before that data becomes the basis of a tax assessment.
In a Review titled Review into the Taxpayers' Charter and Taxpayer Protections, the Inspector General of Taxation states:
… stakeholders have raised concerns that the current EOI processes between Australia and its treaty partners do not explicitly include requirements for the relevant taxpayer or their representatives to be informed. Such notification may facilitate earlier engagement, may provide alternative domestic sources for the required information or limit the scope of the EOI. They are also of the view that being informed about EOI should be a fundamental procedural right of all taxpayers. In their view, where taxpayers are unaware that information has been exchanged, there is no opportunity for them to consider the information, correct any identified inaccuracies or properly contextualise the information before it is applied in the tax assessment process. (p. 120 paragraph 6.15)
While this paragraph is mainly addressing one-off information requests, the same principles apply to Automated Exchange of Information such as FATCA and CRS. In fact, one could argue that the right to be informed is even more important for automated processes as the opportunity for error is greater.