What is form 12b?

Do you mean to say form 12B or 12BB?

Form 12B is an income tax form that needs to be furnished according to Rule 26A by an individual joining a new organisation or company in the middle of the year. The main purpose of the form is to furnish details of the income earned by the individual from the previous employer.

While Form 12BB is a declaration of tax deductions. Employee has to submit this declaration to the employer.

Usually employers ask for a declaration at the start of the financial year to estimate TDS calculations for the whole year. At this time you may not have completed your investments for tax deduction. It is mandatory for employers to collect Form 12BB from employees before allowing them tax deductions. No need to submit to Traces....

Thank you so much. So it is employee responsibility to submit form 12B to new employer.