Google's attitude towards privacy has been criticised by campaigners who are warning of a "race to the bottom" in corporate surveillance of customers.
The search giant's attitude was attacked as being at its worst "hostile" and at its best "ambivalent", following a six-month investigation by Privacy International into the privacy practices of more than 20 internet-based companies.
Google came bottom of the privacy rankings, which included other internet heavyweights such as Apple, eBay, Microsoft and YouTube.
The report, A Race to the Bottom: Privacy Ranking of Internet Service Companies, said the search giant was ranked last partly due to its "aggressive use of invasive or potentially invasive technologies", market dominance and the size of its product range.
The report said Google also gathers and retains large quantities of information about its users and their activities.
A Google spokesman said Privacy International's report is based on "numerous inaccuracies and misunderstandings" about Google's services and the company stands by its record for protecting user-privacy and offering products that are transparent about what information is collected.
Google was the only company to earn the bottom ranking for "comprehensive consumer surveillance and entrenched hostility to privacy" but none of the companies featured in the report got the highest "privacy friendly" ranking.
The report said the overall privacy standard of the key internet players is "appalling" with some companies demonstrating "mindless disregard" for the privacy rights of their customers.