Social Security tax while on F-1 Practical training

If I am working (in Pennsylvania) fulltime on my OPT (Optional Practical Training), after completing my MS, Do I have to pay Social Security tax?
Thanx

If you are on your OPT, you are exempted from Social security tax and medicare tax. Your employee should not be deducting those taxes from your monthly wages/salary. (My employee do not).

You are NOT subject to Social Security and Medicare tax withholding on your wages if:

you have on campus employment, or
you are authorized for Curricular or Optional Practical Training, or
you are authorized for employment due to Economic Hardship
If your employer has withheld these taxes in error, follow these steps:

You must first request a refund of these taxes from your employer. (If your employer is able to refund the taxes, no further action is necessary)
If your employer is unable to refund these taxes, request a statement outlining their denial of your refund.
You do not need to file Form 843 if your employer agrees to refund these taxes.
If you are unable to receive a refund of these taxes from your employer, you may then file Form 843 to request a refund from IRS. Include the following:

a completed Form 843
a copy of your W-2
a copy of the visa page of your passport
a copy of Form I-94
a copy of your work authorization (A copy of your EAD authorizing OPT or Economic Hardship, or a copy of front and back of your Form I-20 or IAP-66 authorizing CPT)
a written statement that you unsuccessfully requested a refund of these taxes from your employer. (This can be the statement you obtained from your employer, or your own statement that you were denied refund of these taxes by your employer and were unable to obtain a statement from them.)

Mailing instructions:
Mail Form 843 along with all documents listed above to:

Internal Revenue Service Center
Philadelphia, PA 19255

I guess there is some confusion. Are you employer or employee. Employee is the one who is doing the job and the employer hires the employee for doing the job. So, it's the employer who can deduct taxes of employee. :-)