But ARM's chief executive played down the threat of export bans. It isn't to do with the ownership of the company, it's all to do with analysis of the product itself, Simon Segars told the BBC. The majority of our products are designed in the UK or outside the US, and the majority of our products don't fall under much of the US export control set of rules. Mr Huang added that ARM had some of the finest computer scientists in the world in Cambridge and he intended to both retain them and attract others to what would become Nvidia's largest site in Europe. The UK prime minister's spokesman said ministers have spoken to both companies, adding that the government would be scrutinising the deal including what it means for the Cambridge HQ. ARM creates computer chip designs that others then customise to their own ends. It also develops instruction sets, which define how software controls processors. It is based in Cambridge but also has offices across the world, including a joint venture in Shenzhen, China. Hundreds of companies license its innovations including Apple, Samsung, Huawei and Qualcomm. To date, ARM says 180 billion chips have been made based on its solutions. When Softbank acquired ARM, it promised to keep the company's headquarters in the UK and to increase the number of local jobs, which it did. Softbank's founder Masayoshi Son described the firm as being a crystal ball that would help him predict where tech was heading. But losses on other investments, including the office rental company WeWork, prompted a rethink. California-headquartered Nvidia overtook Intel to become the world's most valuable chipmaker in July. Until now, it has specialised in high-end graphics processing units (GPUs). These are commonly used by gamers to deliver more detailed visuals, as well as by professionals for tasks including scientific research, machine learning, and cryptocurrency mining. Nvidia is also one of ARM's clients, using its designs to create its line-up of Tegra central processing units (CPUs). Under the terms of the deal, Nvidia will pay Softbank $21.5bn in its own stock and $12bn in cash.