This is how the original RFID chips were used when they were invented back in the 1950s. The military secretly, and illegally, implanted these chips in people, in sinus cavities and in women's uteruses, and then used a network of readers to track a person's movements through the town, factories and so on. They may have been trying to identify people who were suspected of entering restricted areas without clearance or who had stolen documents or radioactive materials.
If you don't believe me but believe the following odd statement from the RFID industry, then you have not done enough research on the 50s and 60s UFO scares. Much of the problem was not about people seeing spaceships, but people who had been drugged and implanted recovering odd memories of bright lights, and being probed.
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RFID technology was solely invented by Charlie Walton in the 1970's and patented in 1973 and 1983 . Although patented many years ago, RFID technology only came to be used more recently in the 2000s