Mainland buyers accounted for almost 20 per cent of the sales in two new private residential projects in the New Territories that offered almost 2,700 luxury flats, a green group says.
Green Sense spokesman Roy Tam Hoi-pong said that, despite the recent government's policy of giving preference to local property buyers, the figures showed "many of the new homes built in Hong Kong are not for locals to live in but to satisfy the investment interests of local and mainland billionaires".
Tam said that in its searches of the Land Registry, Green Sense had found 19 per cent of 1,333 flats sold up to the middle of last month in The Beaumount went to customers with pinyin names as opposed to names written using Hong Kong romanisation. The Cheung Kong development in Tseung Kwan O has 1,777 flats.
In The Riverpark, a 981-flat Sha Tin project by New World Development and MTR Corp, buyers with pinyin names accounted for 18 per cent of 555 sales.
Both are marketed as luxury projects. For example, The Riverpark was sold at an average HK$8,500 per square foot, which this week went up to HK$9,000.
According to Tam, a sign in The Riverpark's showroom read, "selected mainland buyers are given priority in the queue".
Tam said: "We found someone to pose as a Putonghua-speaking visitor, but he couldn't get the priority because he did not have a mainland travel document."
He urged the government to expand its recently announced "Hong Kong property for Hong Kong residents" scheme. For now, this applies to only two sites at the former Kai Tak airport that will go on sale early next year.
The pilot scheme restricts the sale of new homes - and their resale for the following 30 years - to buyers who have Hong Kong residency.
Tam conceded that judging buyers' identities based on only the spelling of their names was not entirely accurate, but believed that this was nevertheless valid as a way of providing a rough estimate.
Real estate agencies including Centaline give regular estimates using a similar method.
However, the method cannot distinguish between speculators and mainlanders who have acquired residency in Hong Kong, and also misses people who buy through companies.
Tam's findings tally with property group Centaline's earlier records, which indicated that for flats worth less than HK$12 million the market share of mainland buyers rose from about 10 per cent in late 2009 to nearly 30 per cent in the past year.
For properties costing more than HK$12 million - including both new and second-hand homes - mainlanders featured in 27.3 per cent of the deals in the July to September quarter.
Tam suggested the government require developers to record buyers' place of residence and submit the data to officials, and assess the housing demands of different groups.