When you have money in a superannuation fund that's invested in a group investment fund, there are some special rules that apply from 1 April 1999. Usually, when a company buys back its own shares, there are rules about how this is treated for tax purposes. However, for superannuation funds with investments in group investment funds, these rules don't apply in the same way.

If you're managing a group investment fund, you had a choice to make before 31 March 1999. You could decide if you wanted the usual rules about share buy-backs to apply to the superannuation funds investing in your group investment fund. If you chose this option, then from 1 April 1999, those rules would apply. But if you didn't make this choice, then the usual rules about share buy-backs wouldn't apply to the superannuation fund's investment in your group investment fund.

This might sound complicated, but it's really about making sure that superannuation funds are treated fairly when they invest in group investment funds. The government wanted to give fund managers a choice about how these investments would be handled for tax purposes.