The Hidden 3rd Party “Vulnerability” in Google Drive | Trend Cloud Security Blog - Cloud Computing Experts

Dropbox and Microsoft’s SkyDrive and Trend Micro’s SafeSync let you keep your copyright and IP rights to the files you upload to their cloud storage. This is a sane and normal approach for businesses. If you keep your own copyright to things you put in the cloud, you can argue that you had a reasonable expectation to privacy, and your cloud files are subject to Fourth Amendment protections even though they are at a third party cloud service.

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Your terms of service for Google Drive absolutely destroy any argument that content uploaded to your cloud storage service has a reasonable expectation of privacy. Therefore, data on Google Drive is not subject to subpoena and is clearly open to viewing by law enforcement under the Third Party Doctrine.