Spiral (formerly Square Crypto)
Companies
Spiral is Block's Bitcoin-focused R&D subsidiary, created by Jack Dorsey in 2019 as Square Crypto and renamed Spiral in 2021. It funds Bitcoin Core developers, creates open-source Bitcoin developer tools, and advances the Bitcoin ecosystem with no profit motive. Key projects include the Bitcoin Development Kit (BDK), Lightning Development Kit (LDK), and research grants to prominent developers like Matt Corallo. Spiral is one of the most significant institutional funders of Bitcoin open-source development.
Details
- Type
- Bitcoin R&D / Open Source Funding
- Public
- No
- Sector
- bitcoin_infrastructure
- Ticker
- Private (subsidiary of Block/XYZ)
- Bitcoin Only
- Yes
- Founded Year
- 2021
- Headquarters
- San Francisco, California
- Key Projects
- Bitcoin Development Kit (BDK), Lightning Development Kit (LDK)
- Parent Company
- Block, Inc.
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Strategy (formerly MicroStrategy)
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Acurx Pharmaceuticals
Acurx Pharmaceuticals (NASDAQ: ACXP) is a US biopharmaceutical company that made headlines in November 2021 by adopting Bitcoin as its primary treasury reserve asset — one of the first pharmaceutical companies to do so. The company approved purchasing $1 million in Bitcoin and has continued to hold BTC alongside its drug development pipeline focused on antibiotics. Notable for crossing industry boundaries to embrace the Bitcoin standard.
aifinyo AG
aifinyo AG is Germany's first pure-play Bitcoin treasury company, announced in October 2025. Founded in 2012 and publicly listed since 2018, the company operates two BaFin-regulated subsidiaries — aifinyo finance GmbH (factoring and leasing) and aifinyo payments GmbH (payment institution) — serving 8,000 business customers through its Smart Billment invoice management platform. The company has adopted a MicroStrategy-style strategy, with UTXO Management as a strategic investor, targeting accumulation of 10,000 BTC by 2027.
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