Grauity

Dear Sir, Need an small clarification. My employer shows Gratuity in offer letter and appraisal letter as part of CTC. But in monthly pay slips Gratuity is not shown but deducted from every employee. And the amount deducted is not deposited anywhere. So if I am resigning and leaving company before completion of 5yrs, am I eligible to claim by deducted Gratuity amount from my employer? Please suggest. Thanks!