Tax departments across the country are keeping a close watch on prices following the July 1 rollout of the goods and services tax (GST). Makers of consumer goods and handsets, as well as some restaurant chains, have all got calls from local tax authorities seeking details of invoices before and after GST as part of the exercise. In order to study prices under the GST, you are requested to send selling price of your top commodity... in the relevant format,” read a notic sent to a company by local tax authorities in Tamil Nadu.

Source - http://economictimes.indiatimes.com