From the very first release on January 8th, 2009, the Bitcoin source code included copyright and licensing information. The software was released under the open-source MIT License, a very unrestrictive license, allowing use of the Bitcoin software in many different use-cases, effectively placing the Bitcoin source code in the public domain from inception. The first copyright information distributed with the first release of the software indicated a claim by “Satoshi Nakamoto”, the infamous pseudonymous entity that created and released Bitcoin to the world:
// Copyright (c) 2009 Satoshi Nakamoto // Distributed under the MIT/X11 software license, see the accompanying // file license.txt or http://www.opensource.org/licenses/mit-license.php.
According to the U.S. Copyright Office, registration of a copyright with their office is voluntary. Regardless of registration, copyright exists from the moment the work is created, and an official registration is only required if you wish to bring a lawsuit for infringement. This establishes the copyright for Bitcoin to be publicly attributed to Satoshi Nakamoto as of January 8th 2009.
This copyright information persisted in the source code through the project’s initial SourceForge days, up through its migration to GitHub and its first commit of license.txt to the newly-created repository there. The next significant change in Bitcoin’s copyright came as a commit on February 12th, 2010 when the date range was updated to include multiple years:
The next significant change came as a source code commit from from Satoshi on December 13th, 2010, updating the copyright from Satoshi themself to, collectively, the Bitcoin Developers:
Beyond this, there were numerous updates to the date range in the copyright as the software aged, as well as a change in filename from license.txt to COPYING in April of 2011. The date range continued to be updated with no other significant changes through the year 2015, when the Bitcoin project changed its name to Bitcoin Core, and updated the copyright notice to reflect the change on May 14th, 2015:
The Core Developers continued to further update the date range every year through 2017, when then on September 13th 2017 a second copyright line was added out of an abundance of caution, re-adding the more generalized copyright by Bitcoin Developers:
You can review the entire change history for the license.txt and later the COPYING file here.
What this history of Bitcoin copyright establishes, is that:
- Copyright was established from the very first public Bitcoin software release, first attributed to “Satoshi Nakamoto”.
- Satoshi later very specifically released this claim on copyright from themself, to, collectively, the Bitcoin Developers.
- Later, the Bitcoin Developers in charge of the software project changed names to Bitcoin Core, and thus changed the copyright to The Bitcoin Core developers to reflect the name change.
- The Bitcoin Core developers re-added the claim on copyright more generally attributed to the Bitcoin Developers, out of an abundance of caution.
- At no point in time did a legitimate claim on copyright to the Bitcoin software not exist.
- Anyone claiming to be Satoshi today has no legitimate claim to copyright as the real Satoshi specifically released their claim in favor of a general claim by, collectively, the Bitcoin Developers.
- Anyone attempting to enforce an alternate claim on copyright, through either modification of this original notice or through a later official copyright filing with the U.S. Patent Office that contradicts this original copyright will fail due to this prior art and claim on copyright existing prior to any later official filing made.