Made from all-natural and sustainable resources by StalkMarket®. Plant-based biopolymer Ingeo™ materials. Double-lined with Natureworks Ingeo™ biopolymer, made from all natural plant sugars. Fully compostable within 60 to 90 days in commercial composting facilities. Meets ASTM D6400 compostable standards and BPI certified. Cedar Grove approved. Not recommended for microwave.