China just made it legal to trap its own tech workers inside the country. New exit rules took effect today. Any citizen China deems a threat to "national technology security" can now be barred from leaving. Anyone who's already left and comes back after doing something Beijing decides harmed its industrial security faces a travel ban up to three years, on their own passport, in their own country. This isn't hypothetical. In March, Beijing already blocked the two co-founders of AI startup Manus from leaving while it reviewed Meta's attempt to buy the company, then forced Meta to unwind the deal entirely. China's own framing calls this protecting "industrial and technological security." Translate that. If you know something Beijing doesn't want leaving with you, you don't get to leave either. Chinese citizens have technically had more travel freedom than during the Cold War for decades. This is Beijing quietly building the legal machinery to take that back, one engineer at a time, dressed up as an export control update.