Section 73 in The Employees' State Insurance Act, 1948
73. Employer not to dismiss or punish employee during period of sickness, etc.
(1)No employer shall dismiss, discharge or reduce or otherwise punish an employee during the period the employee is in receipt of sickness benefit or maternity benefit, nor shall he, except as provided under the regulations, dismiss, discharge or reduce or otherwise punish an employee during the period he is in receipt of disablement benefit for temporary disablement or is under medical treatment for sickness or is absent from work as a result of illness duly certified in accordance with the regulations to arise out of the pregnancy or confinement rendering the employee unfit for work.(2)No notice of dismissal or discharge or reduction given to an employee during the period specified in sub-section (1) shall be valid or operative.
