A year after the implementation of one of the biggest structural reforms - Goods and Services Tax (GST) - two things are seen to remain constant in the new indirect tax regime: one is anti-profiteering, and the\u00a0other constant is tax rate change, experts say. Interestingly, anti-profiteering, which ensures that tax reduction benefit is passed on to customers, is likely to be a constant only as a result of constant\u00a0rate changes in the GST regime. The government has revealed plans of further rate rationalisation as revenue improves - mostly keeping highest 28% limited to demerit or sin goods, which currently has 35 items including air conditioners and large colour TVs. Moreover, the government has also indicated that the GST Council may consider merging 12% and 18% tax slabs into one 14%-15% tax slab. "In the GST regime, rate change is a constant. The government will cut rates or merge two rates as one. And because of this, anti-profiteering becomes a constant; two years for now, but it may be extended in future, given its success or impact," said L Badri Narayanan, Partner, Lakshmikumaran & Sridharan. The National Anti-profiteering Authority (NAA) has been constituted under section 171 of the Central Goods and Services Tax Act, 2017 to decide whether\u00a0the reduction in tax rates or benefit of input tax credit is being passed on to consumers or to the final party. The body will cease to exist after two years as per\u00a0rule 137 of the CGST Rules. However, given the elaborate plan of the government to make several changes in the rates, experts say that it is a possibility for the anti-profiteering body to stay beyond these two years. The NAA was approved on June 18, 2017, about two weeks ahead\u00a0of the roll-out of the GST. Anti-profiteering has been tough on businesses over complaints of not passing GST rate reduction benefits. So far, big names such as\u00a0Hindustan Unilever, Patanjali Ayurved,\u00a0Jubilant FoodWorks, McDonald\u2019s franchisees have been slapped with notices among others. However, penalties have not been imposed in any of these cases and investigation is underway by\u00a0the Directorate General of Safeguards (DGS), which also investigates anti-dumping by importers.