Bolt
Bolt Threads, Inc. was a private biomaterials company that developed Mylo (mycelium-based vegan leather) and Vegan Silk (synthetic spider silk) for luxury and athletic brand partners including Stella McCartney, Hermès, and Adidas before ceasing operations in 2023.
- Company typePrivate
- Founded2013
- HeadquartersEmeryville, United States
- Headcount11–50
- GTM typeB2B
- OfferingHardware or Manufacturing
What Bolt does
Bolt Threads, Inc. was a privately-held biomaterials company founded in 2013 and headquartered in Foxboro, Massachusetts. The company developed two core products: Mylo, a vegan leather alternative made from mycelium (the root structure of mushrooms) grown via proprietary fermentation, and Vegan Silk, a synthetic spider silk protein produced through bioengineering. Bolt's go-to-market was partnership-driven enterprise licensing and co-development with premium fashion and athletic brands — including Stella McCartney, Hermès, Adidas, and Lenzing — targeting the luxury and sportswear segments with sustainable, cruelty-free material alternatives. Revenue mechanics centered on material licensing royalties and limited direct product sales; the most prominent commercial outcome was the Stella McCartney Mylo handbag, of which approximately 100 units were sold at £1,995 each.
Despite raising approximately $476 million across multiple funding rounds from 2012 through 2025 — including a $253 million Series C in September 2021 led by Baillie Gifford — Bolt Threads failed to achieve commercial viability. Total cumulative spending exceeded £160 million before the company paused Mylo production in July 2023. Historical revenue of approximately $3.14 million was dwarfed by a net loss of roughly $65.39 million, implying unsustainable unit economics (~$3 million in cost per bag produced). By 2026, the company's website explicitly states that "The Company is no longer operating," and correspondence routes to a bankruptcy/collection email address. Bolt Threads, Inc. is a distinct entity from Bolt Projects Holdings, Inc. (formerly NASDAQ:BSLK), a separately incorporated company that focuses on biomaterials for beauty and personal care and which itself received a Nasdaq delisting determination in December 2025.
Bolt firmographics
Firmographics- Name
- Bolt
- Legal name
- Bolt Threads, Inc.
- Website
- https://bolt-bslk.com
- Company type
- Private
- Founded year
- 2013
- Operating status
- Closed
- Headcount range
- 11–50 employees
- Short description
- Bolt Threads, Inc. was a private biomaterials company that developed Mylo (mycelium-based vegan leather) and Vegan Silk (synthetic spider silk) for luxury and athletic brand partners including Stella McCartney, Hermès, and Adidas before ceasing operations in 2023.
- Ownership category
- akta.pro rank
Bolt industry classification
Industry- Product category
- Biomaterials
- NAICS
- Fiber, Yarn, and Thread Mills (31311)
- SIC
- Apparel & Other Finishd Prods Of Fabrics & Similar Matl (2300), Textile Mill Products (2200)
- akta.pro primary industry
- Sewing Thread Manufacturing (IMAOAAAH)
Keywords
Where Bolt is headquartered
LocationHeadquarters
- HQ city
- Emeryville
- HQ country
- United States
- HQ region
- North America
Markets served
Bolt business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Technology or R&D, Personnel, Operations, Marketing or Sales
Revenue model
- Material Licensing: Licensing Mylo and Vegan Silk materials to fashion and luxury brands for incorporation into their products.
- Direct Product Sales: Direct sales of consumer products made from Mylo materials, including the Stella McCartney partnership where approximately 100 bags were sold at £1,995 each before production was paused.
Go-to-market motion1 record
Distribution channels1 record
Marketing channels3 records
Bolt product offering
Product offeringCore offering
Bolt Threads developed and manufactured bioengineered materials — specifically Mylo, a leather alternative grown from mycelium, and Vegan Silk, a lab-grown spider silk protein fiber — sold to apparel, luxury, and sportswear brands as sustainable replacements for animal-derived leather and silk. The company commercialized the materials through direct brand collaborations, co-developed products (e.g., Stella McCartney's Falabella bag, Adidas Stan Smith Mylo), and licensing of its proprietary bio-fabricated inputs.
Product overview
Bolt was a biomaterials company that developed sustainable material alternatives for the fashion industry. The company operated two primary product lines: Mylo™ (a mushroom-based leather alternative made from mycelium) and Vegan Silk™ (a synthetic spider silk product). Both products were positioned as sustainable alternatives to conventional animal-derived materials. The company partnered with fashion brands including Stella McCartney, Hermès, H&M, Levi's, Patagonia, and Adidas to develop prototypes. Bolt ceased operations in July 2023.
Differentiator
Problem solved
Functional benefit
Brands
- Mylo: Vegan mushroom leather alternative developed by Bolt Threads, made from mycelium grown in labs from renewable ingredients.
Products and services
- Mylo
- Vegan Silk
Quantifiable outcome
- Approximately 100 Mylo bags sold at £1,995 each before production pause in July 2023
Companies that use Bolt
Customer profileNamed customers4 records
Segments2 records
Ideal customer profiles2 records
Bolt technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature2 records
Bolt partnerships and signals
Strategic signalPartnerships
Three partnerships are on record, tiered flagship and core.
- Stella McCartneyflagshipFlagship partnership where Stella McCartney created garments and accessories from Mylo mushroom leather. The partnership produced a limited edition handbag priced at £1,995, with approximately 100 units sold before production was paused in July 2023.
- HermèscorePartnership with the French luxury goods maker to explore and develop mycelium-based materials for potential use in Hermès products, leveraging their combined expertise in sustainable luxury goods.
- AdidascorePartnership with the German athletic wear company to develop and incorporate mycelium-based materials into sportswear and athletic footwear products.
Scale indicators5 records
Recent moves7 records
Expansion highlights3 records
Bolt competitors and assessment
Company assessmentMarket position
Competitive moat3 records
Key risks6 records
Key highlights4 records
Customer concentration
Bolt social profiles
Digital presenceBolt financial estimates
Financial estimateRevenue estimate
Valuation estimate
Bolt leadership team
Management profileNumber of profiles
Profiles6 records
Bolt funding detail
Funding detailFunding overview
Funding rounds8 records
Investors19 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Bolt M&A and investment
M&A and investmentM&A1 record
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Bolt
What does Bolt do?
Bolt Threads developed and manufactured bioengineered materials — specifically Mylo, a leather alternative grown from mycelium, and Vegan Silk, a lab-grown spider silk protein fiber — sold to apparel, luxury, and sportswear brands as sustainable replacements for animal-derived leather and silk. The company commercialized the materials through direct brand collaborations, co-developed products (e.g., Stella McCartney's Falabella bag, Adidas Stan Smith Mylo), and licensing of its proprietary bio-fabricated inputs.
Is Bolt a public or private company?
Bolt is a private company. It is classified as venture growth investor backed and is currently closed.
When was Bolt founded?
Bolt was founded in 2013. It employs 11 to 50 people.
Where is Bolt based?
Bolt is headquartered in Emeryville, United States, in the North America region.
How does Bolt make money?
Two revenue lines are on record. Material Licensing is the primary driver. The others are direct Product Sales.
Does Bolt have an API?
No public API is recorded for Bolt.
What industry is Bolt in?
Bolt's product category is Biomaterials. Its primary akta.pro industry code is IMAOAAAH, Sewing Thread Manufacturing. Its NAICS code is 31311 and its SIC code is 2300.