Starbucks said Tuesday it is pledging $10 million toward a new initiative to develop a recyclable coffee cup within three years.

Starbucks is teaming up with Closed Loop Partners‘ Center for the Circular Economy to create the NextGen Cup Challenge. The challenge will award grants to entrepreneurs working on ideas that could lead to the development of more sustainable cups.

Starbucks said the challenge represents a the first step toward keeping cups out of landfills and making them recyclable or compostable. Whatever solutions come out of the challenge will be open source, to encourage other coffee companies to join in.

“No one is satisfied with the incremental industry progress made to date, it’s just not moving fast enough,” Colleen Chapman, vice president of Starbucks global social impact overseeing sustainability, said in a statement. “So today, we are declaring a moon shot for sustainability to work together as an industry to bring a fully recyclable and compostable cup to the market, with a three-year ambition.”

Starbucks cups have a plastic coating on the inside, which allows them to hold up under the heat from coffee, but that makes them unable to be recycled in some areas. Starbucks cups are recyclable in several large markets, including Seattle, New York, Boston, San Francisco and Washington D.C. Starbucks is calling on cities to develop consistent recycling and compost policies to ensure that cups can be more widely recycled.

Starbucks said it is in the middle of a six-month trial of a new cup liner made partially from plant-based materials for its paper cups. Starbucks said this is the 13th internal test of this type in just the last year.

The new initiative answers the calls of frequent protesters who have called on Starbucks to develop more sustainable cups. Those groups have shown up at a variety of events, including the 2017 GeekWire Summit where Starbucks CEO Kevin Johnson spoke, and could make an appearance at the company’s shareholder meeting tomorrow.

The groups applauded the recyclable, compostable cup challenge but expressed skepticism, noting that Starbucks has fallen short on past sustainability goals.

“Starbucks today agreed to solve its 4 billion disposable cups per year problem, putting it on the right side of history for forests and climate — we think,” said Todd Paglia, executive director of Stand.earth, a group based in Bellingham, Wash. “This is the third such commitment Starbucks has made — and if they follow through, it will change the impact of its cups and the worldwide cup market. Because this is their third commitment, Stand.earth needs more details from Starbucks about its pledge.”