English Exam Waiver???

I am wondering whether I can get a waiver on English exam by providing an English proficiency proof. I came to the US in 2000 and received two master’s degrees (MBA and MS in IT) in two years. I worked part-time professionally in an English business setting when I was a student in the US and have been working full-time professionally in an English business setting in the US since 2002. Do you think I can get a waiver on the English exam? Does anyone have a sample of the English Proficiency Proof letter?

Thank you very much for your help.

Best,

Eric