The Foundry Group’s Ryan McIntyre (who was a board member of Postini) just announced the venture firm’s investment in browser security startup Authentic8, which is the brainchild of Postini founder Scott Petry and Ramesh Rajagopal (Postini’s VP Corporate Development). Postini offered businesses message security, archiving, encryption, and policy enforcement tools which can be used to protect a company’s email, instant messaging, and other web-based communications platforms. The company was eventually acquired by Google in 2007 for $625 million.

As McIntyre writes, Authentic8 is “a direct descendant of the Postini DNA.” While Positini tackled email security, Authentic8 addresses security in the browser. The startup has created a secure browser called the Disposable Browser (currently based on the Firefox codebase), which runs remotely on a virtual server in the cloud.

From McIntyre’s post: Each time a user accesses Authentic8, a “fresh” browser is built from scratch in private server environment. As a result, any malicious code encountered hits Authentic8’s servers, not the end-user’s. When a browsing session is over, the server instance is trashed, leaving no trace of of a user’s personal data or browsing history behind. Finally, Authentic8 can manage a user’s login and password information, encrypting and submitting login credentials on the user’s behalf. Of course, all communication between the user and the Authentic8 service is encrypted, over their secure protocol.

The goal of Authentic8 is to appeal to businesses who are conscious of employees’ security through browsers. The service is currently in closed-beta and will be opening up to additional beta users in the next few weeks.

Postini offers a number of on-demand communications security and compliance solutions and serves more than 35,000 businesses and 10 million users worldwide. Postini’s services include message security, archiving, encryption, and policy enforcement tools which can be used to protect a company’s email, instant messaging, and other web-based communications platforms. Notably Google was already utilizing Postini technology with Gmail; the acquisition would appear to be a case of Google wanting to own a technology it was already using under license.

The acquisition of Postini comes as a surprise following rumors in June that the company was working towards an IPO.

Dave Girouard, Vice President & General Manager, Google Enterprise wrote on the Google Blog of the need for Google to deliver products that support complex business rules, information security mandates, and an array of legal and corporate compliance issues.

We realized that we needed a more complete way to address these information security and compliance issues in order to better support the enterprise community. That’s why we’re excited to share the news that we’ve agreed to acquire Postini, a company that offers security and corporate compliance solutions for email, IM, and other web-based communications. Like Google Apps, Postini’s services are entirely hosted, eliminating the need to install any hardware or software. A leader in its field, Postini serves more than 35,000 businesses and 10 million users, and was one of our first partners for Google Apps. Their email and IM management services include inbound and outbound policy management, spam and virus protection, content filtering, message archiving, encryption, and more. We will continue to support Postini’s customers and we look forward to the possibilities ahead.

The acquisition is expected to be finalized by the end of the third quarter 2007.

They recently hired a new CFO, Murray Demo, who can handle the IPO process. He was with Adobe for ten years and served as CFO for the last six. According to our source, the company held what is called a “bake off,” which is a selection process for the investment bankers who will market and sell the company’s stock in the IPO, and selected Merrill Lynch as the lead underwriter. Merrill Lynch just happens to be one of Postini’s early customes, so loyalty may have played a part.

Postini’s revenues are rumored to be at around a $75 million run rate, and is “very” profitable.

This is the year that IPOs may make a big comeback. We are tracking a few companies that made it through the downturn, sometimes by resorting to drastic measures to keep the company going, and who are now planning to hit the public markets. Postini will likely not have the $1 billion valuation that Netsuite is looking for, but it is a healthy and profitable company nonetheless.

See the Postini profile here.