This report <https://blocksandfiles.com/2021/06/25/dell-technologies-capital-invests-in-anti-ransomware-startup-calamu/> describes a company called Calamu, whose “safe harbour” technology hashes, compresses, encrypts data, and then breaks it up into three fragments with redundancy. Then it re-encrypts them and stores them in in three separate locations, using different public clouds ... or local file systems. ... Calamu says Protect doesn’t store a complete file in any one location, giving customers full control over who can view their data — even if subpoenaed. That means it cannot be surreptitiously acquired by US law enforcement or intelligence agencies. Now, where have I heard that before? Oh yes ... <https://tahoe-lafs.org/trac/tahoe-lafs>.