Navigating Form 12B: When and How to Share It with Your New Employer?

Hi, I have switched to the new company on 20 May 2023. When do I have to submit Form 12B to the new employer? When will my old employer have to share Form 12B with me? Is it compulsory to share Form 12B with the new employer?
Thank you.

There are a number of forms available under different laws relevant to employment. Therefore, when posting a query, it is advisable to mention under which Act any form is being referenced.

Form 12B of the Income Tax Act

If you are referring to Form 12B of the Income Tax Act, I would like to clarify that it is not mandatory to furnish the form in the exact legal or prescribed format. However, a declaration of income from past employment during the current financial year and the TDS (Tax Deducted at Source) effect on it may be submitted to the new employer. This information will help the new employer determine the appropriate tax slab and the amount of TDS to be deducted from your salary each month.