Major chocolate companies such as Godiva, Lindt and Hershey are failing to keep child labor out of their supply chains, according to a new ranking by activists released on Thursday.

Godiva was rated the worst, followed by Ferrero and Mondalez on a scorecard of efforts to reduce child labor and deforestation published by the activist group Green America.

Mars and Nestle were rated slightly better than Lindt and Hershey, while seven smaller companies received the best grade, including Alter Eco, Divine and Tony’s Chocolonely.

Most of the world’s cocoa is grown by poor family farmers in the West African countries of Ghana and Ivory Coast, where an estimated 1.6 million children work in the industry.

While companies are making efforts to fix the problem, Green America said it is too early to see results for some, while others received low grades for lack of transparency.

“This Halloween and every day, children should be able to enjoy candies that aren’t made by child laborers,” said Charlotte Tate, Green America’s labor justice manager.

“Big brands must do more to tackle these issues, and buying ethically sourced chocolate is one way for consumers to put pressure on brands to change their practices,” she said.