Currently, home owners aged 55 and above who have pledged their property to meet the Minimum Sum requirement have to pay back to CPF the amount they have pledged (with interest) when they sell their property.
From 1st Jan 2009, there will be a change in this rule. Instead of returning just the amount indicated above, they will have to return an amount up to their Minimum Sum requirement. However, if they have withdrawn less CPF money than the shortfall in their Minimum Sum, they will only need to refund what they have withdrawn, including interest (currently at 2.5% p.a.)
This rule change will not affect those who turned 55 before 1st July 1995, or those under the age of 55.
For more details and examples of this rule, you can read this news release by the CPF board.