Capital gains treatment of self generated intangible assets depends on asset classification and legislative amendment timing. Determination of capital gains on transfer of self generated assets depends on whether the asset is goodwill or a right to manufacture, produce or process; the special cost of acquisition rule in clause (a) of s.55(2) applies from distinct assessment years for goodwill and for rights to manufacture, and intangible assets not constituting goodwill must be tested as acquired for consideration or self generated, since self generated intangibles are not chargeable to capital gains until the amendment bringing them within clause (a).