Shares of chip-design software companies like Siemens, Synopsys, and Cadence are rising following the news that the U.S. has lifted export controls that previously restricted sales and business operations in China. This development is expected to improve the financial outlook for these companies, allowing them to resume or expand their activities in the significant Chinese market. The easing of restrictions signals a potential thaw in trade relations between the U.S. and China, boosting investor confidence in the tech sector.