The sale of struggling Silicon Valley startup zGlue’s patents in 2021 was unremarkable except for one detail: The technology it owned, designed to cut the time and cost for making chips, showed up 13 months later in the patent portfolio of Chipuller, a startup in China’s southern tech hub Shenzhen. Chipuller purchased what is referred to as chiplet technology, a cost efficient way to package groups of small semiconductors to form one powerful brain capable of powering everything from data centers to gadgets at home. The previously unreported technology transfer coincides with a push for chiplet technology in China that started about two years ago, according to a Reuters analysis of hundreds of patents in the U.S. and China and dozens of Chinese government procurement documents, research papers and grants, local and central government policy documents and interviews with Chinese chip executives.