In English legal proceedings, a confidentiality club (also known as confidentiality ring) is an agreement occasionally reached by parties to a litigation to reduce the risk of confidential documents being used outside the litigation. The agreement typically provides that only specified persons can access some documents. Setting up a confidentiality club "requires some degree of cooperation between the parties". Confidentiality clubs were described in 2012 as being increasingly common.
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Confidentiality club Wikipedia(Text) CC BY-SA