Gratuity payment

Gratuity is covered under social security act and is statutory right of employee.

It is felt that the act is silent on location.

You have pointed out salary is paid abroad and might be that Salary is not processed in India or Abroad.

Apparently as Singapore office is branch office of the Indian company, there is no change in the status of employer, hence it may not matter salary is paid in India or abroad.

The employee was sent to Singapore on deputation or transfer?

This may also not matter as deputation, transfer are part of service conditions, and counted in tenure of service.

If your company is in kind of business where you have to send them abroad then you may pay gratuity and honor the terms and benefits of employment or employees may feel employer is violator of employment agreement.

Was any social security benefit paid to employee in Singapore?

There are many threads on gratuity in LIC at;

https://www.lawyersclubindia.com/forum/display.asp?cat_id=9&forum_id=49&offset=4#.ULjL-O8yzvo

and some of them touch upon subject cited by you.

Valuable advice of learned experts/members is sought.

How to calculate my gratuity payment?

[(Basic Pay + D.A) x 15 days x No. of completed years of service] / 26

Basic+ DA is as last drawn.

Years of service as def in sec 2(b) (i) (ii), 4 (2)   e.g.

e.g.  if years of service is 5.7 years it may be counted as 6 years.

Valuable advice of learned experts/members is sought.