Foundation Capital led the round, which included new investors Formation 8 and Founders Fund. Bolt Threads has raised a total of $40 million to fuel research and commercialization of its Engineered Silk technology.

Bolt Threads uses proprietary technologies to create Engineered Silk fibers based on proteins found in nature. These programmable fibers, which can be tuned to provide superior comfort and performance, represent the most significant innovation the textile industry has seen for decades. Bolt Threads will use its Series B funding to increase production of better, smarter, more sustainable fibers and grow its team of technology and apparel experts.

'While it's one of the oldest industries in existence, I believe textiles is still ripe for innovation,' said Steve Vassallo, general partner at Foundation Capital. 'Bolt Threads is uniquely positioned to commercialize technology that people have dreamt about for decades. They have developed a way to make Engineered Silk fibers at a commercial scale, at a cost that makes it viable for widespread use in consumer products - something no one else has done. I had been looking into the industry for years before I began working with the founding team in 2010, and I couldn't be more excited about the potential for Bolt Threads' Engineered Silk to transform the textile industry.'

The process of natural silk production inspired the company's co-founders, CEO Dan Widmaier, Chief Scientific Officer David Breslauer and Vice President of Operations Ethan Mirsky. They founded the company in 2009 to create materials with exceptional performance properties.

'We started Bolt Threads based on our fascination with the properties of spider silk, particularly how to use the elegant solutions found in nature to create something even better,' said Widmaier. 'Our technology combines biology and computational methods to create performance fibers with carefully crafted properties. We're very excited to sustainably develop the next generation of performance fabrics that will transform what we wear and how we live.'

Bolt Threads is American-based, conducting research at its headquarters in Emeryville, California and using feedstock grown in the Midwest for production. The company is also collaborating with textile manufacturers in North Carolina to commercially scale production.

The founding team originally received grant funding from multiple sources, including the National Science Foundation, and raised Series A funding from Foundation Capital, Mission Bay Capital, and Zygote Ventures. Each of the Series A participants also contributed to Series B funding, along with Formation 8, Founders Fund, and Alafi Capital.

About Bolt Threads

The material world is about to get a whole new material. Bolt Threads is creating the next generation of performance fibers and fabrics using proprietary breakthroughs in industrial biotechnology. Working at the molecular level, Bolt Threads will transform the textiles market, turning renewable raw materials into products with outstanding properties that meet specific consumer needs. Bolt Threads is backed by Foundation Capital, Formation 8, and Founders Fund, and is based in Emeryville, California.