I am on J1 visa since jun 2007. As per the J1 rule- I am exempted from paying FICA for 2 financial years (Jan-Dec) My employer has been deducting FICA so far. How can I claim it back?

Ask your employer to refund you FICA taxes. Send them e-mail. Now they cannot refund it but you need their answer. Now file Form 843.

Read about filing Form 843: Your U.S. Tax Return: Social Security and Medicare (FICA) Taxes for Non-resident Exempt Individual

Thank you very much... That was helpful

Form 843 requires many attachments, check the list in the instructions.