diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 1da40755a..23f4a7bef 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -24,7 +24,7 @@ SameBoy's main target compiler is Clang, but GCC is also supported when targetin
### Third Party Libraries and Tools
-Avoid adding new required dependencies; run-time and compile-time dependencies alike. Most importantly, avoid linking against GPL licensed libraries (LGPL libraries are fine), so SameBoy can retain its X11 license.
+Avoid adding new required dependencies; run-time and compile-time dependencies alike. Most importantly, avoid linking against GPL licensed libraries (LGPL libraries are fine), so SameBoy can retain its Expat license.
### Spacing, Indentation and Formatting
diff --git a/Cocoa/License.html b/Cocoa/License.html
index b9d7eea45..f8064fa96 100644
--- a/Cocoa/License.html
+++ b/Cocoa/License.html
@@ -29,7 +29,7 @@
SameBoy
-X11 License
+Expat License
Copyright © 2015-@COPYRIGHT_YEAR Lior Halphon
Permission is hereby granted, free of charge, to any person obtaining a copy
@@ -50,6 +50,10 @@
Copyright © 2015-@COPYRIGHT_YEAR Lior Halphon
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
+Except as contained in this notice, the name(s) of the above copyright holders
+shall not be used in advertising or otherwise to promote the sale, use or other
+dealings in this Software without prior written authorization.
+
Third-party Libraries
HexFiend
Copyright © 2005-2009, Peter Ammon
diff --git a/LICENSE b/LICENSE
index 950aa38c6..27b8c8241 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-X11 License
+Expat License
Copyright (c) 2015-2023 Lior Halphon
diff --git a/README.md b/README.md
index 40acf95a4..490b37436 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ Features currently supported only with the Cocoa version:
SameBoy passes all of [blargg's test ROMs](http://gbdev.gg8.se/wiki/articles/Test_ROMs#Blargg.27s_tests), all of [mooneye-gb's](https://github.com/Gekkio/mooneye-gb) tests (Some tests require the original boot ROMs), and all of [Wilbert Pol's tests](https://github.com/wilbertpol/mooneye-gb/tree/master/tests/acceptance). SameBoy should work with most games and demos, please [report](https://github.com/LIJI32/SameBoy/issues/new) any broken ROM. The latest results for SameBoy's automatic tester are available [here](https://sameboy.github.io/automation/).
## Contributing
-SameBoy is an open-source project licensed under the X11 license, and you're welcome to contribute by creating issues, implementing new features, improving emulation accuracy and fixing existing open issues. You can read the [contribution guidelines](CONTRIBUTING.md) to make sure your contributions are as effective as possible.
+SameBoy is an open-source project licensed under the Expat license, and you're welcome to contribute by creating issues, implementing new features, improving emulation accuracy and fixing existing open issues. You can read the [contribution guidelines](CONTRIBUTING.md) to make sure your contributions are as effective as possible.
## Compilation
SameBoy requires the following tools and libraries to build:
diff --git a/SDL/gui.c b/SDL/gui.c
index 5dbfe1047..87deb2fad 100644
--- a/SDL/gui.c
+++ b/SDL/gui.c
@@ -96,7 +96,7 @@ static const char *help[] = {
"Version " GB_VERSION "\n\n"
"Copyright " COPYRIGHT_STRING " 2015-" GB_COPYRIGHT_YEAR "\n"
"Lior Halphon\n\n"
-"Licensed under the X11\n"
+"Licensed under the Expat\n"
"License, see LICENSE for\n"
"more details."
};
diff --git a/iOS/License.html b/iOS/License.html
index 3bec255a6..bc7ad9aa2 100644
--- a/iOS/License.html
+++ b/iOS/License.html
@@ -29,7 +29,7 @@
SameBoy
-X11 License
+Expat License
Copyright © 2015-@COPYRIGHT_YEAR Lior Halphon
Permission is hereby granted, free of charge, to any person obtaining a copy
@@ -49,5 +49,9 @@
Copyright © 2015-@COPYRIGHT_YEAR Lior Halphon
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
+
+Except as contained in this notice, the name(s) of the above copyright holders
+shall not be used in advertising or otherwise to promote the sale, use or other
+dealings in this Software without prior written authorization.
\ No newline at end of file