Seaweed Packaging Company Sway Closes $2.5M Raise Led by Valor Siren Ventures

The round is joined by Conservation International Ventures, Alante Capital, and BAM Ventures to support the development and piloting of compostable plastic replacements.

BERKELEY, Calif.--()--Sway, the California-based materials company producing seaweed-based, home-compostable replacements for single-use plastic packaging, has announced its initial funding round of $2.5 million. Led by Valor Siren Ventures and supported by Conservation International Ventures, Alante Capital, BAM Ventures, and other industry-aligned investors, the raise will support Sway’s development of scalable and sustainable replacements for thin-film plastic packaging derived from petroleum.

Sway is forging the material and cultural dimensions of a plastic-free future. 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 rapidly 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.

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.


Julia Marsh (Co-Founder & CEO | Sway): “At Sway, we are building the next stage in the evolution of plastic. 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.”

Jon Shulkin (Fund Manager | Valor Siren Ventures): “The Sway team is building a material that stands out from the rest. While current offerings require brands to make painful compromises — in cost, performance, or true sustainability — Sway is designing products to make the plastic-free transition seamless and affordable for their customers. We look forward to supporting Sway’s mission of bringing sustainable and scalable plastic replacements to market.”

Janice-Renee Yoshioka (Director, Blue Economy Investments | Conservation International Ventures): “Through its seaweed-based bioplastic solutions, Sway has the potential to reduce reliance on petroleum-based plastics and the harmful effects of plastic pollution on lands and waters. Conservation International Ventures is proud to support Sway’s commitment to developing innovative packaging alternatives that promote restorative seaweed farming practices and livelihoods across Latin America and globally.”

Christopher Krohn (Portfolio Director, Circular Economy | IDEO): “We have greatly enjoyed working with Sway as a winner of the Beyond the Bag Challenge, led by Closed Loop Partners, Managing Partner of the Consortium to Reinvent the Retail Bag, which includes CVS Health, Target, and Walmart, along with other industry leaders. This year, we have witnessed Sway’s impressive progress on material formulation and customer engagement, and look forward to seeing their first pilots with mission-driven, culturally influential brands in 2022.”

Craig Dudenhoeffer (Chief Innovation Officer | Sustainable Ocean Alliance): “Sustainable Ocean Alliance is dedicated to restoring the health of the ocean in our lifetime — and to propelling ventures like Sway in their inspiring work to get us there. Regenerative supply chains are a critical piece of our path towards a sustainable future. We’re thrilled to invest in Sway, one of our Ocean Solutions Accelerator alumni, as they scale their positive impact.”

Industry Relevance

  1. Annually, approximately 500 billion plastic bags are used worldwide (Plastic Oceans).
  2. Approximately 180 billion polybags are produced every year to store, transport, and protect garments, footwear, and accessories. Less than 15 percent of polybags are collected for recycling (Fashion For Good).
  3. The Ellen MacArthur Foundation’s Global Commitment has already mobilized over 500 signatories that are determined to cut down plastic consumption, including companies representing 20% of all plastic packaging produced globally. Signatories include Nestlé, PepsiCo, The Coca-Cola Company, Walmart, and Unilever, as well as packaging producers Amcor and Berry Global (Ellen MacArthur Foundation).
  4. Seaweed can sequester up to 20 times more carbon per acre than trees (Harvard University). If seaweed forests and farms covered just 9% of the ocean, they would sequester the entire planet’s annual carbon emissions (Ocean Foresters).

About Sway

Sway is a materials company based in Berkeley, CA. It was founded in 2020 by designer Julia Marsh (CEO), sustainable development practitioner Matt Mayes (COO), and former Chobani CBO Leland Maschmeyer, who is also co-founder of global design agency COLLINS. Born from their frustration with the shortcomings of existing plastic alternatives, Sway targets thin-film plastic packaging, the hardest-to-replace plastics on the market. Sway products are derived from seaweed, fully bio-based, nontoxic, high-performance, and rapidly compostable in home and industrial compost environments.

Learn more about Sway at their website, or at @swaythefuture on Instagram, Facebook, Twitter, and LinkedIn.

Product images can be found in this folder.


Please send all press inquiries to Russell Reed,

Release Summary

Sway has announced its initial funding round of $2.5 million led by Valor Siren Ventures.


Please send all press inquiries to Russell Reed,