As DC expands its digital footprint via its DC Universe subscription service, sales are falling flat for the publisher in one area: its own comics.

DC co-publisher Jim Lee noted in an interview during Comic-Con International: San Diego that digital comic sales haven't grown like the publisher had hoped. "On the digital side, I think it's been pretty flat in recent years," Lee said. "Which is a little disheartening."

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Lee acknowledged subscriptions to the publisher's DC Universe platform were on the rise, but noted the impact on digital sales. "A lot is moving to subscription, and that is having a downward pressure on transactional sales," Lee noted. "But I think it's discouraging in general because everyone talks about digital being the future."

"If there's anything that should continue to grow year-in, year-out, it should be that channel," Lee continued. "The fact that it's kind of plateaued and we've hit a wall speaks to a lot of different things. We need to reinvent what we're doing digitally."

"The subscription service that we're doing on the DC Universe platform is part of that."

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In addition to streaming services, subscribers to the DC Universe platform have access to a library of over 20,000 digital comics, according to the publisher's website. That site is separate from the publisher's DC comics site, where digital comics are available for purchase.

"We just have to get better at marketing to people that know our characters, love our characters, but aren't buying comics," Lee said.

(via ICv2.com)