Is physical contact between Indian men acceptable?

I understand that there is a cultural difference in personal space between Americans and Indians, but an Indian contractor working in the U.S. is making physical contact with me on a regular basis. The contact is subtle such as: leaning over my shoulder, pulling his chair close to me, standing behind me with hands on my shoulders, etc. I have not noticed this when he is working with others in the same room. In American culture, I would consider his contact to be flirtatious and bordering on unacceptable. I don't want to make a fool of myself or make things more uncomfortable if this is just a cultural difference.