Sway Raises $2.5M for Seaweed Packaging


Berkeley-based Sway is looking to break our habit of using non-recyclable plastic bags.

Sway, the Berkeley, CA-based materials company producing seaweed-based, home-compostable replacements for single-use plastic packaging, has announced its initial funding round of $2.5 million. The raise will support Sway’s development of scalable and sustainable replacements for thin-film plastic packaging derived from petroleum.

160 million tons of plastic bags, wrappers and pouches are produced worldwide each year, but only 1-3% are recycled. These flexible, thin-film plastics remain in nature for centuries, clogging waterways and harming human and aquatic life. Born from their frustration with the shortcomings of existing plastic alternatives, Sway is targeting thin-film plastic packaging, the hardest-to-replace plastics on the market.

Sway’s products are derived from seaweed, fully bio-based, nontoxic, high-performance, and rapidly compostable in home and industrial compost environments. By harnessing the regenerative power of seaweed, a carbon-absorbing and habitat-building resource, Sway intends to offer a naturally carbon-negative and highly accessible bioplastic.

This initial financing will allow Sway to accelerate the development of their first two products — high-performance, rapidly compostable polybags and retail bags — leading to initial pilots with influential and mission-aligned partner brands in 2022. The raise also signifies a major investment in the nascent seaweed industry, which could play a major role in combating climate change through carbon sequestration and ecosystem restoration.

Strategic Investment

The round is led by Valor Siren Ventures, an early-stage investor in sustainability, food, food technology, retail, and retail technology. They are joined by several strategic investors including Conservation International Ventures, an impact investing vehicle of Conservation International that provides financing to enterprises that contribute to healthy ecosystems; Alante Capital, a fund investing in sustainable innovations for apparel production and retail; BAM Ventures, a fund founded by the co-founder and former CEO of The Honest Company; and Bryan Meehan, former CEO of Blue Bottle Coffee. The full list includes the Sustainable Ocean Alliance, Centre Street Partners, C3 Capital, and other climate tech, ocean health, and circular economy investors.

“At Sway, we are building the next stage in the evolution of plastic,” said Julia Marsh, Co-Founder & CEO. “We often talk about the ‘plastic problem,’ but it is only a symptom of a much deeper dependency on petroleum. We are building a material as functional and accessible as traditional plastic but derived from a benevolent resource instead. With the regenerative power of seaweed, we plan to replace petroplastic — for good.”

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