A loophole in reforms to Hong Kong's smoking law means as many as 71 cigarette brands can still carry the banned descriptions 'light' and 'mild' in a development that has angered lawmakers and anti-smoking campaigners. Under a so-called 'grandfather clause' - that allows an old law to continue to apply - tobacco companies will still be able to use any trademarks taken out in Hong Kong before the new law takes effect. Medical sector legislator Kwok Ka-ki said the loophole had rendered the reforms meaningless. 'I thought it was just going to be one or two brands with the descriptors which were going to be exempted from the ban, but it wasn't until I asked the government that they told me there were 71. I was very surprised and I am very angry,' Dr Kwok said. He said debate over the grand-father clause had initially focused on Mild Seven, which uses the word 'mild'. But the clause - incorporated into draft amendments to the bill - had opened the floodgates to other brands which had registered their 'light' and 'mild' lines as separate trademarks. Dr Kwok said other brands with trademarks overseas could also apply for exemption from the ban under Hong Kong's obligations to the World Trade Organisation's agreement on trade-related intellectual property rights. The new law, expected to be passed when the Legislative Council resumes after summer, aims to ban the flavour descriptors as they may mislead smokers into believing the products are less harmful. Among the leading brands expected to slip through the loophole are Philip Morris' popular Marlboro Lights, a trademark taken out in 1991; British American Tobacco's (BAT) Kent Super Lights, whose trademark was taken out in 1993; and Mild Seven, sold by Japan Tobacco, which has spearheaded opposition to the ban. Many popular cigarette brands have trademarks that are more than 20 years old. Other brands have even older trademarks - the obscure BAT brand Marvel Milds dates back to 1937. Dr Kwok said the official reason for the grandfather clause - to avoid the possibility of lengthy and expensive lawsuits by tobacco firms to defend their intellectual property - was not satisfactory since such lawsuits had been thrown out in nearly every jurisdiction where they had been brought, including the EU, Australia and Canada. A US district court on Thursday ordered a ban from January on the use of descriptors such as 'light' from cigarette packaging.