Not true I’m not going to name off of them but there are several reasons or laws that would prevent disclosure. Here is just one of many I can think of off the top of my head. If the acquisition of shares is part of an ongoing merger or acquisition deal, there can be certain "safe harbors" or exceptions. For example, when the acquisition of shares is part of a planned merger or acquisition (and not intended to influence the target company before the deal closes), the parties involved may not need to file a 13D immediately. In this case, the 13D filing requirement might be delayed until the deal has reached a certain stage or the transaction has been completed. This is often referred to as the "transactional exception."