Just google demergers and a lot of possibilities come up.

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Everyone's tax situation is unique so always check so no surprises come up.

ATO site on demergers. Seems to be optional for most situations regarding CGT. See if you can understand this for your situation

A demerger involves the restructuring of a corporate or fixed trust group by splitting its operations into two or more entities or groups. Under a demerger, the owners of the head entity of the group (that is, the shareholders of the company or unit holders of the trust) acquire a direct interest (shares or units) in an entity that was formerly part of the group (the demerged entity).

While a demerger may give rise to a capital gain or loss, you:

• can choose a rollover for any capital gain or loss you make under the demerger
• must calculate the cost base and reduced cost base of your interests in the head entity and your new interests in the demerged entity immediately after the demerger.
  Just google demergers and a lot of possibilities come up.