A mainland businessman and his wife are suing HSBC's Swiss private banking unit after losing more than US$5 million on high-risk investment products. In a writ filed with the High Court, Qi Weibao and his wife, Cheng Yicong, from Tianjin, claim false representation by bank employees led them to buy accumulators and equity-linked notes, losses on which caused their investment to dwindle from an initial US$5.15 million to just US$59,218 as markets fell in 2008. An accumulator is a high-risk vehicle in which investors buy a security, currency or commodity at regular intervals at a fixed price below the prevailing market value for the term of the contract. They make money if the market remains stable or rises, but losses can be huge if it falls. Equity-linked notes are linked to the performance of stocks. The couple say in the writ that they visited the Hong Kong office of HSBC Private Bank (Suisse) in March 2007, where they told staff they were inexperienced investors with little knowledge of shares, securities or derivatives. The couple, who have an autistic son, wanted a prudent investment plan with moderate risk. They later opened an account and deposited US$3 million. In a letter, the bank characterised the couple's investment profile as balanced with a medium tolerance for risk. The couple say they were told that if they did not agree to be described as 'professional investors', they would miss out on good investments. A bank working with a 'professional investor' is released from some of its responsibility to provide information on risk. Between March and May 2007, another bank employee urged them to buy nine equity-linked notes. In the same year, a bank representative urged the couple to buy 30 accumulators and an additional 10 equity-linked notes. A bank employee allegedly said of the couple's investment choices that 'while it may sound scary, in fact it is not so'. But the market collapse in 2008 saw the couple suffer huge losses. The couple's counsel, Martin Lee Chu-ming SC, wrote that HSBC, though its employees, breached the 2006 code of conduct issued by the Securities and Futures Commission and failed in its duty to explain the nature of the investment and the risk. The couple are among a group of protesters from Hong Kong and the mainland who fought for compensation for losses in the 2008 crash. The bank took out an injunction to ban group members from approaching its premises or defaming it.