diff --git a/README.md b/README.md
index 04f6c960d..01a94dd59 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,28 @@ The autogenerated OSAL user's guide can be viewed at <https://github.com/nasa/cF
 
 ## Version History
 
+### Development Build: 5.1.0-rc1+dev262
+
+- Adds test cases for `OS_ObjectIdFinalizeDelete`, `OS_DeleteAllObjects`, and others to get 100% line and function coverage on VxWorks and shared/portable layers.
+- Ensures APIs check for `NULL` inputs or have documentation stating that a null value is allowed.
+- Adds timeout to static analysis check and adds format check. Removes old .travis.yml and updates badges in readme.
+- Adds Code QL analysis on push to main and pull requests (to main)
+- Cleans commented-out code in tests to address static analysis warnings
+- Initializes local variables to avoid returning uninitialized values from stubs and address static-analysis findings
+- Replaces two local return codes defined as `uint32` with `int32` to resolve static-analysis warnings
+- Simplifies switch statements based on previous checks. Removes unreachable, dead code to resolve static-analysis warnings
+- Terminates  unit test macros variadic lists with `NULL` to address CWE-121 CodeQL warning
+- Adds a check to send the semaphore to avoid unreachable code
+- Adds a status return to `OS_ConsoleAPI_Init` so debug warnings will get reported correctly on errors.
+- Declares `DummyVec` as static to avoid warning and returning stack allocated memory when returning `VecTbl` in `OSC_INUM_TO_IVEC` stub
+- Updates types in `os-impl-no-symtab.c` to match latest APIs
+- Updates types in `os-impl-no-symtab.c` to match latest APIs
+- Fixes missing `NULL` terminations and applies the standard "sizeof" pattern where appropriate. No longer truncates filename in `OS_ModuleInfo`.
+- Fixes `%u` conversion in RTEMS so to address build warning
+- Create a wrapper around `memchr()` that mimics the non-C99 function `strnlen()` defined in POSIX-2008. Use this instead of `strlen()` whenever the string being checked either originates in or will be copied into a fixed-length array buffer. No behavior changes except if a bug causes strings to be unterminated.
+- No behavior change, applies the standard formatting using `clang-format`
+- See <https://github.com/nasa/osal/pull/774>
+
 ### Development Build: 5.1.0-rc1+dev221
 
 - Fixes `printf` format to correctly build in RTEMS-5.
diff --git a/src/os/inc/osapi-version.h b/src/os/inc/osapi-version.h
index 5708be8ca..9923b82c3 100644
--- a/src/os/inc/osapi-version.h
+++ b/src/os/inc/osapi-version.h
@@ -30,7 +30,7 @@
 /*
  * Development Build Macro Definitions
  */
-#define OS_BUILD_NUMBER   221
+#define OS_BUILD_NUMBER   262
 #define OS_BUILD_BASELINE "v5.1.0-rc1"
 
 /*