One needs to understand that the term CTC is a cosmetic figure used to present the company in a better position to employees than it actually is. It stands for Cost to the Company and should not be equated with the Gross Salary of the employee. Only when it is shown under the term Gross Salary can you challenge the employer; otherwise, no.
As far as the Payment of Gratuity Act, 1972 is concerned, it is quite clear that one must complete a full 5 years to stake a claim for gratuity, as rightly pointed out.
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