Running Commentary on the SP Movements., page-9559

CGT treatment when scrip-for-scrip rollover doesn't apply

When scrip-for-scrip rollover does not apply, you have a CGT event when you exchange (dispose of) your existing shares.
To correctly calculate the capital gain or loss for your original shares, you'll need to keep records (in addition to the usual records) showing the parties to the arrangement, the conditions of the arrangement, and the capital proceeds. As each takeover or merger arrangement is different, you need to obtain full details of the arrangement from the parties involved.
Your capital proceeds for your original shares are the total of:

• the market value of the shares you received at the time of the takeover, and
• the money you received (if any).

The cost of acquiring the shares in the takeover or merged company is the market value of your original shares at the time you acquire the other shares, reduced by any cash

Example: Takeover where shares were exchanged for shares with a cash proceed and the scrip-for-scrip rollover doesn't apply
In October 2010, Desiree bought 500 shares in DEF Ltd. These shares are currently worth $2 each. Their cost base is $1.50.
XYZ Ltd offers to acquire each share in DEF Ltd for one share in XYZ Ltd and 75 cents cash. The shares in XYZ Ltd are valued at $1.25 each. Accepting the offer, Desiree receives 500 shares in XYZ Ltd and $375 cash.
The capital proceeds received for each share in DEF Ltd is $2 ($1.25 market value of each XYZ Ltd share plus 75 cents cash). Therefore, as the cost base of each DEF Ltd share is $1.50, Desiree will make a capital gain of 50 cents ($2 − $1.50) on each share – a total of $250.
The cost base of the newly acquired XYZ Ltd shares is the market value of the shares in DEF Ltd ($2) less the cash amount received ($0.75); that is, $1.25 each or a total of $625 (500 × $1.25).