The holding company made its investment a year and a half before Microsoft plopped down $240 million for a 1.6% position last fall--a move that valued the company at some $15 billion. Under that metric, IPG's piece looks to be worth at least $75 million. (It's unclear how much it paid initially for its stake in June 2006.) But if privately held Facebook follows through with plans to go public, the value could soar.

When IPG took its small stake in Facebook, the site still wasn't open to all comers, and MySpace was arguably a hotter social networking property. IPG said at the time that it viewed its involvement less as a financial maneuver and more as an opportunity to use the site to test various advertising, marketing and promotional tactics for clients targeting the younger set. (Those rights were part of the deal.)

"We wish (our stake) was a little bigger ... but at the time we invested in Facebook, we were doing it for strategic reasons to learn what was going on," said IPG CEO Michael Roth on Monday at an investor event.

"We've made a nice profit so far based on what you read about it in terms of the market value ... but the key there is learning what's going in this new media (landscape)," he said.

In addition to Facebook, IPG has made a range of other "intelligence" investments looking to gain insight into emerging spaces, such as online video (Joost) and word-of-mouth marketing (BzzAgent).

Also on Monday, Roth continued to pitch investors on IPG's integrated offerings--suggesting that all its operations are offering a full palate of services to clients, including the new linchpin digital expertise. The capabilities are "embedded in all our different offerings," he said.

He was largely referring to IPG's traditional agencies, which have been proficient at developing 30-second spots for decades. (The company has a range of digital specialists, notably R/GA.)

Not only do global shops such as DraftFCB and the McCann operations offer integrated services, but Roth said so-called "independent" U.S.-focused shops are also up to speed. Those include Campbell-Ewald, which works with Chevrolet; the Martin Agency, which represents UPS and Geico; and Deutsch.

As for the economy's impact on IPG going forward, Roth expressed cautious optimism--acknowledging that it's a "difficult environment," but also one that offers opportunities. In a recession, he said, if IPG can use its own optimization tools to demonstrate ROI, the company could steer clients in a direction where they continue to spend strategically.

"If you can prove that your advertising dollars are effective in the marketplace, why would you diminish the spend when you need to enhance revenue?" he said. "It's our job to prove that the tools that we have are capable of measuring the effectiveness of the spend."

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