The search giant told vnunet.com that the acquisition was completed earlier this month, but declined to provide specific terms of the deal.
A notice on GreenBorder's website says that the company has stopped selling its security software, and that customers will be supported until their existing contracts expire.
The software uses a virtualisation technique known as a 'sandbox', in which the browser runs entirely within a separate secured system.
This prevents any attacks or exploits from using flaws in the browser to access system resources and run malware.
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