The online equivalent of a physical room that is set up for viewing confidential documents when performing due diligence in such matters as mergers and acquisitions, rounds of venture capital, IPOs, court trials and other legal transactions. The virtual data room (VDR) is a highly secure website to which data are uploaded and available to qualified participants by strong passwords. Search with Restrictions The software that implements a virtual data room offers a variety of search functions with numerous restrictions. For example, certain parts of documents may be excluded from viewing, copies may be prevented, and visitor actions may be thoroughly logged by time, date and documents viewed. See extranet.