diff --git a/lib/tbb_2020.3/STAN_CHANGES b/lib/tbb_2020.3/STAN_CHANGES
index 8de7574b633..fa31216f77d 100644
--- a/lib/tbb_2020.3/STAN_CHANGES
+++ b/lib/tbb_2020.3/STAN_CHANGES
@@ -2,3 +2,12 @@ This file documents changes done for the stan-math project
 
 - drop -g flag from makefiles for release mode builds to decrease size of binaries
 - Add `tbb::` to line 252 of `task.h` to fix a build failure with gcc 13. This was done upstream in https://github.com/oneapi-src/oneTBB/pull/833
+
+- build/windows.inc patches for RTools make:
+  - L15 added:
+    add ifeq (true,$(USING_RTOOLS))
+      export SHELL = sh.exe
+    else
+      export SHELL = cmd
+    endif
+  - L25,L113,L114 added additional '/' to each cmd flag