conversion of share corp to non-share corp would not cause a share disposition if no share cancellation and the rights of the shareholders were not substantively altered
trust deed amendment by court order to permit addition of corporations that were only indirectly owned by family beneficiaries did not trigger a disposition/ such addition triggered disposition of trust interests but without proceeds
extinguishment of trust interests on their renunciation is a disposition of the renounced interest, but resulting variation of trust to accelerate distribution entitlements is not