Professor in different university

[Moss13]

I graduated 4 years ago but I wanted to study more. So I planned to apply for the masters program and while I was searching for my old professors to ask for ROL, I found out they no longer teach at the school I graduated. They've moved to other university. Is it okay to still ask them for my recommendation?

[ion_exchanger]

I don't see why not. Professionals move all the time, and are still used as referees for their students at their previous institutions. They would just note in their letter that they taught you at X university.