LRS General Discussion, page-6420

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This is done to create a loss to offset against a gain already derived, or expected to be derived, in a tax return.A wash sale is different from normal buying and selling of assets because it is undertaken for the artificial purpose of generating a tax benefit for the current financial year.The ATO can identify wash sales through access to data from share registries and crypto asset exchanges.When the ATO identifies this bhaviour, the capital loss is rejected, resulting in an even bigger loss to the taxpayer.

Imagine having the capital loss rejected