Forrest Sorrels, the Secret Service agent in Dallas, drove around with Zapruder trying to find someone who could develop the film and then another group who could make copies. Then after making copies they went back to Kodak (the first group) to develop those. The obvious act would have been to immediately take the camera from Zapruder and send it to Washington for examination. Don't let him develop it, don't let others see it, don't let him make copies that you'd have to control.
Instead, Sorrels "allowed" Zapruder to develop and keep the in camera original, make three first generation copies, and let probably a dozen or more people see the film before obtaining it. It being two *copies* and NOT the original. He allowed Zapruder to keep the original and one copy.
Here's a nice summary. "Erwin" was Erwin Schwartz, Zapruder's business partner.
