Ask HN: Incubating a startup in India while working for a Big C

I recently relocated from US to India. The job agreement that I signed to work for at a big company seems to be very restrictive. The agreement says that anything I create even outside of the normal work hours is company's property. And, I should check with the company if anything I do might affect them or not. The company also wants to reimburse my internet and cell phone charges. I do not know if this "benefit" is related or not. Is this normal practice in India? What do other people do to incubate a startup while working at a Big C during normal hours? The big company is a nice company otherwise and the work there is also interesting work. However, I want to create something on my own computer in my free time. I am concerned that the big company might create trouble, if they come to know about it. Any thoughts?