I got PhD degree last May and currently employed as an assistant professor in a college.
I am employed with my OPT card and I am in US since 2001.
As far as I know I do not have to pay Social Security and Medicare taxes but I could not find any document at IRS web site to convince my employer.
Can you please tell me if I am right about that and if so can you please refer the relevant official IRS document?
Thanks a lot.
SAE

I believe the waiver from having to pay social security or medicaire taxes applies only if you are employed by the college where you are studying, and for a maximum of 20 hours/week. It may well be that once you got your PhD you no longer fall into the category for exemption?

Because you have been in the U.S. since 2001, you LOST your exemption from paying Social Security and Medicare taxes on 31 December 2005.

This means that you ARE liable for Social Security and Medicare taxes in your current job if your co-workers at the university are also paying these taxes.

Sorry!