diff --git a/CHANGES.md b/CHANGES.md
index 506692ab..d4e9ba9e 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,6 @@
 # Imath Release Notes
 
+* [Version 3.1.9](#version-318-May-31-2023) May 31, 2023
 * [Version 3.1.8](#version-318-May-22-2023) May 22, 2023
 * [Version 3.1.7](#version-317-March-1-2023) March 1, 2023
 * [Version 3.1.6](#version-316-november-7-2022) November 7, 2022
@@ -17,8 +18,21 @@
 * [Version 3.0.0-beta](#version-300-beta-march-15-2021) March 15, 2021
 * [Inherited History from OpenEXR](#inherited-history-from-openexr)
 
+## Version 3.1.9 (May 31, 2023)
+
+Patch release that fixes an correct .so version number introduced in
+v3.1.8. All Imath library functionality is compatible with v3.1.8.
+
+This release also reverts
+[#305](https://github.com/AcademySoftwareFoundation/Imath/pull/305)\],
+which inadvertently introduced additional python bindings in v3.1.8
+that altered the ABI of ``libPyImath``. ``libPyImath`` is now
+ABI-compatible with v3.1.7 and previous releases.
+
 ## Version 3.1.8 (May 22, 2023)
 
+**NOTE: this version has an incorrect .so number and should not be used. Use v3.1.9 instead.**
+
 Patch release that addresses miscellaneous minor compiler/build/doc
 issues and extends test coverage.
 
@@ -42,6 +56,8 @@ issues and extends test coverage.
 
 ## Version 3.1.7 (March 1, 2023)
 
+**NOTE: this version has an incorrect .so number and should not be used. Use v3.1.9 instead.**
+
 Patch release with miscellaneous bug/doc/build fixes. In particular:
 
 - Support for relative prefix in pkg-config
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d6a3ab5e..1ffdccbb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,7 +14,7 @@ endif()
 
 # Imath version
 
-project(Imath VERSION 3.1.8 LANGUAGES C CXX)
+project(Imath VERSION 3.1.9 LANGUAGES C CXX)
 
 set(IMATH_VERSION_RELEASE_TYPE "" CACHE STRING "Extra version tag string for Imath build, such as -dev, -beta1, etc.")
 
@@ -38,8 +38,8 @@ set(IMATH_VERSION_API "${Imath_VERSION_MAJOR}_${Imath_VERSION_MINOR}")
 #   2. API added:     CURRENT+1.0.AGE+1
 #   3. API changed:   CURRENT+1.0.0
 #
-set(IMATH_LIBTOOL_CURRENT 31)
-set(IMATH_LIBTOOL_REVISION 0)
+set(IMATH_LIBTOOL_CURRENT 29)
+set(IMATH_LIBTOOL_REVISION 8)
 set(IMATH_LIBTOOL_AGE 0)
 set(IMATH_LIB_VERSION "${IMATH_LIBTOOL_CURRENT}.${IMATH_LIBTOOL_REVISION}.${IMATH_LIBTOOL_AGE}")
 set(IMATH_LIB_SOVERSION ${IMATH_LIBTOOL_CURRENT})