Gratuity doubt

Dear frds / experts,

1) Is there is any procedure for Pvt Ltd companies to come under Gratuity Act? If so what are they?

2) Is Gratuity Amt is payable by employer from his pocket to employee? Or should be deducted from employee in his monthly salary, which should be paid after 5 years?
Because in some cases I heard 4.81% Gratuity deducted from employees monthly salary? which one is correct? plz advice me with relevant details.

thanks in advance.

-Maya.