The Registered trademark initially get for 10 (Ten) year and on the expiry of 10 (Ten) year required renewal for father 10 year this is continues follow the same process for every10 (Ten) years expiration. So the registered trademark name maintain in the register of the trademark registry.
The renewal trademark application must be filed before the expiry of the trademark to the appropriate trademark registry. Before the expiry the trademark registry send notice the trademark registered owner regarding expiry of your trademark. If, not renewal your trademark than your brand / trademark will remove for the trademark register.
To extension of protective rights
To bar form any one to get registration of same similar brand.
To get Brand value
To maintain Intangible assets
To maintain brand equity