The Taiwan Stock Exchange (TWSE) aims to sign a memorandum of understanding (MOU) on supervision and cooperation with its counterparts on the Chinese mainland at an early date, said TWSE's chairman Schive Chi Wednesday. Schive Chi said he hoped stock exchanges in Taiwan, Hong Kong, Shanghai and Shenzhen could set up a platform to enable local stocks be traded by more investors. The Taiwan authority's measures introduced in August last year to encourage more Taiwan firms to return to list on the island had attracted at least 17 Taiwanese-owned companies based on the mainland to apply to list, according to the chairman. Now, some companies listed elsewhere began to apply to issue Taiwan Depository Receipt (TDR), he said. Hong Kong-listed Want Want and Ju Teng have already issued shares in Taiwan this year. The Taiwan Stock Exchange welcomed mainland investors to invest in the island's stock market as most obstacles on trading across the Taiwan Strait had been eliminated, he said. The Taiwan authority opened up the island to mainland investment earlier this year with 100 categories of manufacturing, service and infrastructure sectors in the initial opening-up list. It also started to open its securities and futures market to institution investors on the mainland. 