15 July 2013
Yes penalty may be imposed. It is at the discretion of AO.
Please check sec 271F.
271F. If a person who is required to furnish a return of his income, as required under sub-section (1) of section 139 or by the provisos to that sub-section, fails to furnish such return before the end of the relevant assessment year, the Assessing Officer may direct that such person shall pay, by way of penalty, a sum of five thousand rupees.
Penalty under section 271F is applicable if your income before Chapter VIA deductions exceeded the basic exemption limit[requirement in 139(1)]
If income before chapter VIA deductions not exceeded the basic exemption list it is not mandatory to file return under section 139(1) and consequently penalty 271F is not applicable to you