Denied Bouns After Tendering Resignation.

Dear All ,
Thanks in advance , i have a query regarding compensation .
I work in IT Pvt Company , After one week on my resignation , company announce bonus for Employee for their past contribution toward organisation. As i am working for last 6 year with organisation i thought i will be entitled for this.
But as i haven't received bouns i asked HR regarding , they said that employee who tendered their resignation are not eligible .
I want to know can company decide this on its own.
For better understanding i want to add further information.
1. I am still working with company under my notice period , so when bonus was announced i was legal on roll employee of company.
2. There was no prior information regarding this action ( that employee who tendered resignation are not eligible)
Is there any legal act under labor or employee relation act which i can refer to.

First find out whether the bonus is paid in terms of the Payment of Bonus Act. If not, then I do not think you have much remedy.

Please let me know the Financial Year for which Bonus is Paid (2015-16 or 2016-17), is your Basic/DA/VDA is less than Rs21,000/-PM, to be eligible for The Payment of Bonus Act, 1965?
Under the Payment of Bonus Act, an Employee who has resigned from the Service is also eligible on Pro rata basis

Thanks Ritesh &
SRINATH
No i do not fall under Payment of Act salary limit.