I am discussing provisions of sec23 and also up to date relevant circular and notification.

• Persons engaged exclusively in supplyinggoods/services/both not liable to tax. Eg:X is a trader and he is trading100% in alcohol for human consumption.His turnover is 2 crores.Therefore X isnot liable to obtain registration as per sec23(1)(a)
• Persons engaged exclusively in supplyinggoods/services/both which are wholly exempt from tax.
• Agriculturist to the extent of supply of produce out of cultivation of land.

According to my interpratation while computing  aggregateturnover ‘intrastate supply of goods agricultural produce grown out ofcultivation of land by family members shall not be included because they usedthe wording ‘to the extent of’

Eg.MR.A has an intra state supply of agricultural produce(own effort) Rs.15 Lakhs,Intrastate supply of exempt goods Rs.10Lakhs,& taxable supplies is Rs.5 Lakhs.He is not supposed to take gst registration because turnover does not exceed 20lakhs i.e 10 plus 5 =15 lakhs.while computing  aggregate turnover ‘intrastate supply of goods agricultural produce grown out of cultivation of land by family members shall not be included

• Specified category of persons notified by the government

Relevant  circulars,  notifications,  clarifications,   issued  by  Government are as follows.

1.Notification  No. 5/2017 –- Central  Tax  dated 19.06.2017  regarding  exemption from registration  to  persons engaged  only  in making  taxable  supplies where  total  tax is  liable to  be paid  on  reverse charge  basis

2.Notification  No.  32/2017 38/2017 –– Central  Tax  dated  15.09.2017  (amended  by  Notification  No. Central  Tax  dated  13.10.2017)  regarding  exemption  from  registration  to  a casual  taxable  person  making  taxable  supplies  of  handicraft  goods.

 3.Notification  No. 65/2017 Central  Tax  dated 15.11.2017  regarding  exemption from compulsory registration to suppliers of  services  through an  ecommerce platform

4.Notification No.7/2017@IT dated 14.11.2017 regarding exemption for job worker engaged in making  interstate supply of job work services except jewelers business

5.Notification No.8/2017@IT dated 14.09.2017 regarding  exemption  from registration to  a  person  making  interState  taxable  supplies  of  handicraft  goods.

regarding exemption  from registrationto  a person  making  interState taxable  supplies  of handicraft  goods.

6.Notification No.10/2017 Integrated  Tax  dated  13.10.2017  regarding  exemption  from to  persons  making  interstate supplies of taxable services not exceeding 20 lakhs is exempt from obtaining registration

7.Notification No.56/2018-Central Tax, dt. 23-10-2018 Seeks to supersede Notification No. 32/2017-Central Tax, dated 15.09.2017 link given below

.https://documentcloud.adobe.com/link/track?uri=urn%3Aaaid%3Ascds%3AUS%3Aa76f0180-29b5-4d28-91b8-54da5caeef30

Thanks and Regards