Symantec, the makers of the Norton anti-virus software, looks set to acquire MessageLabs for $695 million as it seeks to expand its internet services interests.
Symantec provides a number of online backup services, storage and remote access products which allow people to access information and applications on their PCs from any location where there is web access.
MessageLabs produces security products for email, messaging and the internet in general and has around eight million end users.
The deal still has to be approved by the regulatory body, but could go ahead by the end of the year if all goes well.