Henderson Land Development is increasing the size of its planned Tseung Kwan O joint-venture development in a move that could generate it an additional $2 billion from property sales. Its massive residential project, to be jointly developed with Sun Hung Kai Properties (SHKP) and Chinachem Group, is planned for a site it expects to be granted by the Government in exchange for its Letter B land exchange certificates. Henderson executive director Wan Man-yee said that because it had contributed more land entitlement claims to the joint venture, Henderson would be entitled to a higher profit share. Letter B certificates were issued by the Government to village landlords from the 1960s to 1983 as part of a large-scale rural redevelopment programme for the New Territories. Holders could exchange the certificates for money or use them in lieu of cash to acquire development land in new towns. In the past two decades, Hong Kong's big four developers have been buying certificates from individuals to swap in bulk with the Government for large tracts of government land. Mr Wan said Henderson had now won a private tender to buy up a large number of Letter B certificates held by the Tsing Shan Monastery and Tsing Wan Kun Monastery in Tuen Mun. These certificates would entitle Henderson to another 60,000 square feet of agricultural land, he said. Under government guidelines, rights to every five sq ft of agricultural land can be converted into two sq ft of development land in a new town. This means Henderson would be entitled to another 24,000 sq ft of new town land from the monastery sale. It is also believed the company recently acquired rights to another 46,000 sq ft of new town land from other individuals. Mr Wan did not disclose the acquisition price or the exact number of Letter B documents acquired but said the company had accumulated the certificates over the past few months. Henderson already held outstanding rights to 30,000 sq ft of new town land, which means it is now entitled to 100,000 sq ft of land. When pooled together with outstanding certificates held by SHKP and Chinachem, the trio were entitled to one large site, of which Henderson would own about 30 per cent, Mr Wan said. The Government was originally expected to award the consortium a combined 260,000 sq ft site. It will now grant it a 330,000 sq ft site in Area 57 of Tseung Kwan O. Based on today's market price of $4,000 per sq ft for completed flats in Tseung Kwan O, analysts said Henderson could expect to reap an estimated $2 billion from the additional gross floor area. The final size of the site granted could be further increased. Developers have been told they can continue accumulating Letter B certificates until next Monday - the deadline fixed by the Government before calculating developers' final holdings. The Government aims to redeem all remaining outstanding Letter B certificates before the handover next year. It will also grant a 250,000 sq ft site at Area 55 in Tseung Kwan O in exchange for the certificates owned by Nan Fung Development - the biggest Letter B certificates holder.