Snapchat is encouraging brands to run longer video by buying bigger packages of ads.

According to sources, Snap has started pitching brands on a new type of ad package called sequenced messaging, a type of sequential advertising, in recent weeks. The new ad pricing bundles video ads together so brands can run back-to-back video ads with different creative within Discover—the app's hub of daily content from publishers including Cosmopolitan, CNN and The Daily Mail—to tell one story. For example, one media buyer described how marketers can cut up a 30-second spot into three 10-second ads that run consecutively.

"Think about taking a 30-second asset and getting it cropped up into three 10-second spots. I'm going to buy three back-to-back ads, and I'm going to tell this sequential story," said a digital ad buyer who was recently briefed on Snapchat's ad packages and spoke with Adweek on condition of anonymity. "I think it becomes unique in regard to storytelling. These guys are trying to get away with this idea of, 'Maybe if you watched three seconds of the first video, five seconds [of the second video] and then 10 seconds to finish the story, that's good as long as you get the point of the narrative.'"

Sequential advertising is a sophisticated targeting tactic used by digital marketers. It zeros in on people who have previously seen or engaged with an ad and then follows up with a series of messages. The practice is commonly used with Facebook and Twitter.

However, Snap's pitch has a twist. Instead of relying on complex tagging, tracking or pools of audiences, sequenced messaging ads are bought as a takeover of a Discover channel with contextual targeting.

"What's interesting here is that this becomes part of the DNA of a buy," explained another digital exec briefed on Snapchat's plans. "You're starting to think through a linear story or a progression that can be told in a couple of steps, which is quite a bit different than your typical execution that you'd see elsewhere in social."

The source added that the new ad buys are only sold directly through Snapchat (as opposed to being sold through the company's API) at premium prices that require "early commitments for a full-service execution."

A Snapchat rep confirmed that sequenced messaging is open to all advertisers but added that the app's audience buys—which include look-alike, interest and email list targeting—are the most popular types of ad packages.

Ilana Nolte, president of WPP-owned m/Six, said her shop has been working with fashion retailer David Yurman to run targeted ads within Discover. With the addition of sequenced messaging, "we have the ability to split our ad up into three different segments and serve them one segment and then retarget those individuals with another segment to continue the story," she said. "It allows us to create a better engagement with that consumer."

Entertainment brands are typically some of the first advertisers to test Snapchat ads, and Sony Pictures and Universal Pictures have both used Snapchat's sequenced messaging tools.

Universal Studios is currently running a campaign for the horror movie Split within Cosmopolitan's Discover channel that breaks up a 30-second teaser for the film into three ads. And Sony Pictures is running a similar campaign for Resident Evil: The Final Chapter that breaks up the movie's content into shorter bits within the IGN Discover channel.

Sequential advertising could also help Snapchat overcome some of the persistent creative challenges in getting brands to create short, vertically oriented video. In theory, a big brand marketer could cut up a 30-second TV spot for Snapchat, but agencies are also interested in creating longer-form custom content for the app.

"I would want to see brands that were thinking more about creating three 10-second vignettes tied together, almost episodic, as opposed to saying, 'I've got a 30-second TV spot. I'm just going to chop it into pieces of 10 seconds and run it,'" said Lisa Cucinotta, director of social strategy and business development at Horizon Media. Cucinotta said she has heard a bit about sequential ads but has not seen Snapchat's full packages.

"The thing I always wonder about with sequential is how much people actually realize that it is sequential," she said. "With Facebook mobile, you're still scrolling up and down through a feed, whereas with Snapchat, yes, you are still scrolling, but it's a little more real estate, and it's a little more of a controlled experience. So, it could be a very evocative storytelling format."

While Snapchat's sequential ads are initially limited to video ads, another digital exec briefed by Snapchat said he expects the format to also soon involve Snapchat's recently launched lead-generation tools for deep linking and autofill.

"It's mostly for video, but eventually it makes sense to move someone down the funnel and help at the end of the day increase efficiency," the exec said.