Base License Comparison
All four variants share the same AI authorship uncertainty acknowledgment, patent non-assertion, trade secret risk acknowledgment, and jurisdictional savings clauses.
| IDK | IDK-Attribution | IDK-Weakleft | IDK-Strongleft | |
|---|---|---|---|---|
| WTF variant | IDK-WTF | IDK-Attribution-WTF | IDK-Weakleft-WTF | IDK-Strongleft-WTF |
| Similar to | CC0 / Unlicense | MIT / Apache-2.0 | GPL-3.0 | AGPL-3.0 |
| Type | Maximally permissive | Permissive | Copyleft | Strong copyleft |
| Public domain dedication | Yes | No | No | No |
| Simultaneous multi-license grant | Yes (15 permissive) | Yes (9 attribution) | Yes (7 copyleft) | Yes (AGPL-3.0) |
| Attribution required | No | Yes (with 30-day cure) | Yes (license notice) | Yes (license notice) |
| Closed-source derivatives | Allowed | Allowed | Must share source | Must share source |
| Copyleft (share-alike) | No | No | Yes | Yes |
| Network interaction clause | No | No | No | Yes |
| Patent non-assertion + grant | Yes | Yes | Yes | Yes |
| AI authorship uncertainty | Yes | Yes | Yes | Yes |
| Trade secret risk acknowledged | Yes | Yes | Yes | Yes |
| Copyleft compatibility grant | Yes (one-way) | Yes (one-way) | N/A (is copyleft) | N/A (is copyleft) |
| Copyleft as contractual backstop | N/A | N/A | Yes | Yes |
| SPDX Identifier | LicenseRef-IDK-0.0.1 |
LicenseRef-IDK-Attribution-0.0.1 |
LicenseRef-IDK-Weakleft-0.0.1 |
LicenseRef-IDK-Strongleft-0.0.1 |
Which One Should I Use?
IDK
Maximum freedom. No requirements at all.
Use when you want your work to be as free as possible with no conditions. Similar to placing code in the public domain.
IDK-Attribution
Freedom with credit. Like MIT but for AI-assisted code.
Use when you want to allow any use (including commercial and closed-source) but require that your name and the license notice be preserved.
IDK-Weakleft
Share-alike for distributions. Like GPL.
Use when you want derivative works to remain open source. Modifications must be shared under the same terms when distributed.
IDK-Strongleft
Share-alike for SaaS too. Like AGPL.
Use when you want the strongest copyleft. Even network deployments (SaaS) must offer source code to users interacting over a network.
WTF Wrappers (With These Footnotes)
Every base license has a corresponding WTF variant for projects that include third-party code. The WTF wrapper:
- Incorporates the base license by reference (applies to your original work only)
- Defines the boundary between "Original Work" and "Third-Party Work"
- Includes a Dependency Schedule listing each third-party component and its license
- For copyleft variants, classifies each dependency as "combined" or "aggregated" to determine copyleft scope
| Base License | WTF Variant | Extra Columns in Dependency Schedule |
|---|---|---|
| IDK | IDK-WTF | Standard (Work, Version, License, Holder, Location, Source, Method) |
| IDK-Attribution | IDK-Attribution-WTF | Standard |
| IDK-Weakleft | IDK-Weakleft-WTF | Standard + Integration Type + Compatibility |
| IDK-Strongleft | IDK-Strongleft-WTF | Standard + Integration Type + Compatibility |
Compatibility Between Variants
Arrows show one-way compatibility (code can be incorporated in the direction of the arrow).
| From \ To | IDK | IDK-Attribution | IDK-Weakleft | IDK-Strongleft |
|---|---|---|---|---|
| IDK | — | Yes | Yes | Yes |
| IDK-Attribution | No | — | Yes | Yes |
| IDK-Weakleft | No | No | — | Yes |
| IDK-Strongleft | No | No | No | — |
IDK and IDK-Attribution include one-way copyleft compatibility grants covering GPL, LGPL, AGPL, MPL, EPL, EUPL, and the IDK copyleft variants. IDK-Weakleft is compatible with its 7 fallback copyleft licenses (including IDK-Strongleft). IDK-Strongleft is compatible only with AGPL-3.0 (its sole fallback).