Not 100% sure.. but if incase you have used it after acquiring Canadian citizenship, there might be penalty while applying for Surrender/OCI process.
Check the BLS site:
http://www.blsindia-canada.com/renunciation_ppt.php
The Mission/Consulate would levy penalty if the Indian passport has not been cancelled for more than 3 years, or if it was utilized to visit India or any other consular service was obtained after acquiring foreign nationality. The penalty would be in addition to the Renunciation Fee. Following are the provisions relating to penalty:
1. Penalty for retention of Indian passport after acquiring Canadian citizenship for a period in excess of three years from the date of acquiring Canadian citizenship
a) If your Passport expired on or before 31 December, 2004 - no penalty
b) If your passport expired on or after 1 January, 2005 - C$ 343
(Note: Retention Penalty (C$343) is different from Renunciation Fee (C$ 240). The latter needs to be paid by those who acquire foreign nationality on or after 1 June, 2010.)
2. Penalty for travelling on Indian Passport after acquiring Canadian citizenship is C$ 343 for each time, subject to a maximum of C$ 1711
3. Penalty for getting Indian Passport renewed or re-issued after acquiring Canadian citizenship is C$ 856 for each such renewal or reissue.
4. Penalty for obtaining any miscellaneous passport service (name change, etc.) on Indian Passport after acquiring Canadian citizenship is C$ 343 for each such service.
