Hulu CEO Mike Hopkins chalked up the exceptions to rights held by studios on select series. “They have other commitments that they couldn’t free them up for a complete commercial-free offering,” he said, adding that the service will clearly delineate the exceptions to users before they stream those series.

Other series that will have pre-roll include four ABC series: “How to Get Away with Murder,” “Grey’s Anatomy,” “Once Upon a Time,” “Agents of SHIELD,” and an NBC series, “Grimm.”

Hulu is making the move in response to subscriber complaints voiced in various forms of consumer research about having to pay yet still watch ads. Earlier this month, a Parks Associates survey found that half of Hulu subscribers have canceled service over the past 12 months, compared to just 9% for Netflix over the same span.

The new subscription option brings Hulu in line with its commercial-free rivals Netflix, which remains several dollars cheaper than Hulu depending on which rate its own subscribers pay, and Amazon Prime, which charges $99 per year for access to its content library in addition to free two-day shipping.

From the article "Hulu Adds (Mostly) Ad-Free Subscription Service" by Andrew Wallenstein.