Samsung SDS Co., a key unit of the country\'s largest conglomerate Samsung Group, said Friday that it has decided to merge with a sister firm to boost overseas expansion. In a regulatory filing, Samsung SDS said the merger with Samsung SNS Co. will help beef up business competitiveness and make inroads into overseas markets such as China. Samsung SDS, one of the group\'s unlisted affiliates, provides information and communications technology services at home and abroad, while Samsung SNS specializes in corporate and home networking. Samsung Electronics Co., the group\'s flagship unit, is the largest shareholder of Samsung SDS with a 21.67 percent stake. The merger came days after Cheil Industries Inc, the group\'s another key unit, said it would sell its fashion business to unlisted affiliate Samsung Everland in a bid to focus on electronics materials. Last month, Cheil Industries said it would acquire Germany-based Novaled AG, a world-class provider of organic light-emitting display technologies and materials, in a deal valued at around 173 billion won (US$159 million). Samsung Group has been seeking to fortify its control on electronics components and materials as it battles global rivals such as Apple Inc. in the rapidly changing mobile industry.