TaxTMI 
TaxTMI 
TaxTMI 
Ground realities:
Ground reality is that many of tax payers (particularly businessman, non-accounts, law and tax professionals, salaried persons, even old professionals etc.) are not comfortable with and cannot or do not want to take burden of tax compliance and therefore the function is assigned to another person.
Many of tax assesses are not in habit of regularly looking at email and other messages. Many may not even log in to email account to receive and reply emails on regular basis.
Some persons (like author himself) had few email addresses but on regular basis only one email address is logged and other are logged on very casual and irregular basis.
Even in case of a group of several related assesses tax work is done by one or few designated persons. Therefore, one mobile phone and one email id is used for several tax assessee.
The purpose of tax department:
The purpose of tax department to send messages on mobile phone and emails is that the taxpayer is quickly informed and the taxpayer is expected to quickly respond. This purpose can be best achieved only if mobile phone number and email address of the person who look after tax matter is given. If mobile phone number and email id of some other person is given, it is difficult to have quick action and response.
To ensure better accountability it can be prescribed that the mobile phone number of assessee and his email id are also registered as own mobile phone and email id. At option of assessee this can be registered as secondary mobile phone and email id. Whereas primary mobile phone number and email id can be for the person who is looking after tax matters of assesse.
If one mobile phone and one email id is used for several such persons, than it will be easy to regularly receive email and act upon them.
One mobile phone and several assessee:
Generally tax matters are looked after by one person t\for several other persons. Even if the tax matters are looked after by family members it is found that one or few of family member look after tax matters of all family members.
Similarly, in case of business house only few of people are made responsible for tax compliance.
In case of professionals working for clients, one professional and few of his assistants would be working for compliance of tax clients.
Therefore, it is practice that one mobile phone is tagged for several assessee (PAN). This is because the person who is working for tax compliance and is responsible must receive all messages on his mobile phone.
One email address for several assesses
Similarly one email id of such person can be used for compliance and communication for several assesses.
Administrative convenience:
One mobile phone and one email id for several assesses is to ensure proper compliance and control by a responsible person. For example in a ground of companies one of Accounts Officer is made responsible for such compliance. Therefore email id of such person and his mobile phone number is given.
In fact for simplicity and ease to administer it is advisable that a separate mobile phone number and email id be used for several of associated persons who have to make compliance.
Recent development:
Recently from on or about 22nd September 2017 when tax payers want to access their account on website of income-tax department, they are being asked to update their information on website. There is also requirement that on mobile phone and one email address should not be used for more than prescribe number of accounts / PAN. Author remember that earlier larger number of PAN could be and were tagged with one mobile phone and one email id (It maybe that there was no limit). Later on this was restricted to 10 PAN per mobile phone and per email id. This also caused lot of difficulty.
More PAN numbers should be allowed per mobile phone and email id:
If the government really want to make business easy, particularly tax compliance easy, it must be left to the tax payers and their people to decide about number of PAN which one want to keep tagged with one mobile phone and one email id.
Government want to make large and strong data base by way of PAN. Therefore, it should be made easy to work with mobile and email id as may be considered by taxpayers suitable to them instead of imposing such unreasonable requirements.
In any case limit of three PAN is very low.
Some people have apprehensions that just to favour mobile phone companies –mobile phone manufacturers and mobile phone service providers the government has reduced number of PAN which could be linked to one PAN.
The discretion should be left upon the taxpayer and practioners:
Discretion about number of PAN that one want to tag with his mobile phone number and email address should be left upon the tax payer and tax professionals. Restrictions on maximum number should be removed.