"We don't have the scale for that," he said. "But we don't want to turn away ad dollars."
Admittedly, there are worse problems than having too much advertiser demand, but no publisher likes to leave money on the table.
This week, Portfolio will move to address that issue and join an audience-reach program offered by Adsdaq, an ad exchange. The program lets Portfolio track its visitors using cookies and find those same users through the Adsdaq exchange when they're on other business-oriented sites and pages. Portfolio essentially will build a reach-extending network on an ad hoc basis, as advertiser demand dictates.
The deal underscores the blurring roles in the online advertising space. Not only are sellers such as Mr. Brandt becoming buyers of inventory through exchanges, but major buying firms such as Group M and Havas are launching media-trading platforms that allow them to do the kind of targeting and parsing of inventory among clients normally reserved for, well, sellers. As Martha Stewart Living Omnimedia co-CEO Wenda Harris Millard said in a speech earlier this year, "My space is your space."
Even as audiences fragment, marketers continue to look for targeted scale. But scale and quality often seem at odds. This deal is one of many that traditional publishers are trying in order to make their web presences viable businesses.
"Brand marketers that advertise on television are used to reaching millions of viewers in a single hour on a given day," said William Morrison, partner and senior internet analyst at ThinkPanmure, in an e-mail. "Large websites on the internet may reach 20 million users in a month, but the number they reach in a given day or hour is typically a fraction of that amount."
Some publishers, such as Martha Stewart and Forbes, have opted to solve the scale-quality issue by curating vertical ad networks -- groups of like sites for which they can sell inventory. Mr. Brandt said he decided against that tactic since the margins are set and often lower than in an exchange, thanks to revenue splits. He also said an exchange offers greater flexibility.
"There's less risk to the publisher because we only buy inventory once we've sold the campaign," he said, adding that Portfolio will be clear about which impressions he's selling are on Portfolio and which are culled from the exchange; they will also be priced accordingly.
The idea behind the exchange concept is to give sellers and buyers better insight into the supply and demand for online advertising. Some exchanges, such as Yahoo's auction-based Right Media Exchange, tend to operate more as funnels for remnant inventory. Adsdaq is trying to create marketplace for premium inventory; it lets publishers come in and set prices. If a publisher is getting 75-cent CPMs from an ad network that sells remnant impressions, the publisher can offer that inventory for $1.25 on the exchange and see if anyone picks it up. If not, it can still dole it out to the remnant ad network. Adsdaq was born out of contextual targeting technologist ContextWeb and touts the integration of that technology as another point of difference.
"We're not doing a pure arbitrage but adding value, a contextual layer, aggregating pages from hundreds of sites around a certain context," said Chief Product Officer Shanthini Sarkar. She said the exchange runs 5 billion impressions today and reaches about 54% of U.S. internet users. It works with 7,000 sites, including 150 of the top 250 ComScore sites.