A comapany with a trademark uses a .in in INdia

[chrome]

Can I register the same domain .co.in
INmobi.in
Should I /Might I register a domain like Inmobi.co.in

 

[pubdomains.in]

If the company has a trademark - you may be liable for INDRP case (buying in bad faith) thus not recommended.
On the other hand if you have a trademark by that name - you can certainly opt to purchase .co.in and other variants!

 

[Ceres]

I notice that it's becoming more common for businesses to register terms with the domain extension (eg: .in or .com etc). One reason for doing this is to prevent them from losing the domain in an INDRP or UDRP case etc.

 

[Jeff]

Your goal should be to buy domains that have meaning to many people / companies, not just one company. Going down the route you suggest is a legal minefield.