This is the last recourse for the owners, who have fought the $548 million sale to the bitter end since it was approved by the Strata Titles Board (STB) in 2007.

Minority owners of the 607-unit, 99-year leasehold estate at Alexandra Road appealed STB's decision in the High Court, but this was dismissed by Justice Choo Han Teck last June.

Senior Counsel Michael Hwang, engaged by Tan Tan Chin Hoe & Co to act for the 10 owners, argued that before amendments last year to laws governing collective sales, former HUDC estates had not been intended by Parliament to be covered by these laws.

Another point of contention was the date used to calculate the age of the development, to determine if the estate needed 80 or 90 per cent consent for an en bloc sale.

Currently, an application for an en bloc sale can be made if there is consent from the owners holding at least 80 per cent of share value if the development is more than 10 years old, and 90 per cent if the development is less than 10 years old.

Mr Hwang argued that since Gillman Heights only got its certificate of statutory completion in 2002, it needed 90 per cent.

Currently, about 87 per cent of owners have signed the collective sale agreement.

Senior Counsel Andre Yeap of Rajah & Tann, who was acting for the purchasers - CapitaLand, Hotel Properties and two private funds - said, however, that it was obvious the age of the development was older than that since it was completed in 1984-1985.

The public gallery was packed with residents at the Tuesday morning hearing at the Court of Appeal.

The three judges who presided over the hearing - Chief Justice Chan Sek Keong, Judge of Appeal Andrew Phang and V K Rajah - said they would reserve judgement until 4.30pm on Wednesday.