Functional Source License 1.1 (Apache-2.0 future)
Source-availableSPDX identifier:
FSL-1.1-ALv2OSI ✗Data updated Sep 26, 2026In plain words
Source-available: any use except a competing product, and each release becomes Apache-2.0 two years later.
Analogy: A shop window whose items become free for everyone after two years.
Pros
- + Short and predictable
- + Code becomes open source after two years
Cons
- - Not open source
- - "Competing use" can be hard to judge
Well-known projects using it
5 well-known projects in our map use this license.
Permissions
- Modification
- Private use
- Converts to open source later
Conditions
- Keep copyright notice
Limitations
- No liability
- No warranty
- Production use restricted
Extreme scenarios · Code licenses
- A1Blocked by licenseA cloud vendor sells your project as a managed service
- A2Blocked by licenseSomeone forks it and distributes a closed-source competitor
- A3With conditionsEmbedded in a closed-source SaaS backend (not distributed)
- A4With conditionsLinked into a closed-source app or firmware and distributed
- A5Not addressedSomeone promotes a modified version with your name or trademark
- A6With conditionsSomeone sells unmodified copies
- B1Blocked by licenseA user sues you for patent infringement and keeps using the code
- B2Blocked by licenseA contributor asserts patents on their contributed code
- B3Not addressedA cross-border dispute: governing law and venue
- C1With conditionsYou later relicense or sell commercial licenses (contributors signed no CLA)
- C2Blocked by licenseYour code is merged into a GPL-3.0 project
- C3Blocked by licenseYou use a GPL-3.0 dependency and still ship under this license
- C4With conditionsThe project is abandoned and someone forks it to continue
- C5With conditionsYou want to block only big companies or competitors
- C6Not addressedKey code was written by an employee and the employer objects
- D1Blocked by licenseSomeone removes copyright or attribution notices
- D2AllowedSomeone modifies files without marking the changes
- D3With conditionsInternal modification, no distribution and no external service
- D4With conditionsUsed for military, surveillance or other uses you object to
- D5Not addressedUsed by a sanctioned entity
- D6Not addressedYour code is used to train an AI model
Worst-case radar
- 1Stops free-riding67
- 2Stops closed forks75
- 3Patent protection100
- 4Adoption friction63
- 5Hard to relicense50
Computed from the scenario matrix. Higher means more of that property, not "better".
Compare with…
Official text
Only the official text is legally binding. We do not translate license texts.
Functional Source License 1.1 (Apache-2.0 future)
# Functional Source License, Version 1.1, ALv2 Future License
## Abbreviation
FSL-1.1-ALv2
## Notice
Copyright ${year} ${licensor name}
## Terms and Conditions
### Licensor ("We")
The party offering the Software under these Terms and Conditions.
### The Software
The "Software" is each version of the software that we make available under
these Terms and Conditions, as indicated by our inclusion of these Terms and
Conditions with the Software.
### License Grant
Subject to your compliance with this License Grant and the Patents,
Redistribution and Trademark clauses below, we hereby grant you the right to
use, copy, modify, create derivative works, publicly perform, publicly display
and redistribute the Software for any Permitted Purpose identified below.
### Permitted Purpose
A Permitted Purpose is any purpose other than a Competing Use. A Competing Use
means making the Software available to others in a commercial product or
service that:
1. substitutes for the Software;
2. substitutes for any other product or service we offer using the Software
that exists as of the date we make the Software available; or
3. offers the same or substantially similar functionality as the Software.
Permitted Purposes specifically include using the Software:
1. for your internal use and access;
2. for non-commercial education;
3. for non-commercial research; and
4. in connection with professional services that you provide to a licensee
using the Software in accordance with these Terms and Conditions.
### Patents
To the extent your use for a Permitted Purpose would necessarily infringe our
patents, the license grant above includes a license under our patents. If you
make a claim against any party that the Software infringes or contributes to
the infringement of any patent, then your patent license to the Software ends
immediately.
### Redistribution
The Terms and Conditions apply to all copies, modifications and derivatives of
the Software.
If you redistribute any copies, modifications or derivatives of the Software,
you must include a copy of or a link to these Terms and Conditions and not
remove any copyright notices provided in or with the Software.
### Disclaimer
THE SOFTWARE IS PROVIDED "AS IS" AND WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING WITHOUT LIMITATION WARRANTIES OF FITNESS FOR A PARTICULAR
PURPOSE, MERCHANTABILITY, TITLE OR NON-INFRINGEMENT.
IN NO EVENT WILL WE HAVE ANY LIABILITY TO YOU ARISING OUT OF OR RELATED TO THE
SOFTWARE, INCLUDING INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES,
EVEN IF WE HAVE BEEN INFORMED OF THEIR POSSIBILITY IN ADVANCE.
### Trademarks
Except for displaying the License Details and identifying us as the origin of
the Software, you have no right under these Terms and Conditions to use our
trademarks, trade names, service marks or product names.
## Grant of Future License
We hereby irrevocably grant you an additional license to use the Software under
the Apache License, Version 2.0 that is effective on the second anniversary of
the date we make the Software available. On or after that date, you may use the
Software under the Apache License, Version 2.0, in which case the following
will apply:
Licensed under the Apache License, Version 2.0 (the "License"); you may not use
this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed
under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
CONDITIONS OF ANY KIND, either express or implied. See the License for the
specific language governing permissions and limitations under the License.