diff --git a/src/CsSig/Analyzer/README.md b/src/CsSig/Analyzer/README.md
index 1d45afb..064bb48 100644
--- a/src/CsSig/Analyzer/README.md
+++ b/src/CsSig/Analyzer/README.md
@@ -33,6 +33,10 @@ All `*.cssig` files in the project are included automatically and together defin
 API surface. Set `<EnableCsSigAnalyzer>false</EnableCsSigAnalyzer>` to opt out. A project with no
 `.cssig` files enforces nothing.
 
+For multi-targeted projects, name a file `<name>.<tfm>.cssig` (e.g. `PublicApi.net8.0.cssig`) to
+apply it only when building that target framework. Unqualified files (e.g. `PublicApi.cssig`) apply
+to every TFM, so put the shared surface there and the TFM-specific surface in qualified files.
+
 You don't write the file by hand: create an empty `PublicApi.cssig`, build (every public member reports
 `CSSIG002`), then invoke the code fix → **Fix all** to generate it from the current surface. Apply
 the same fix to keep it current as the API grows.
diff --git a/src/CsSig/Analyzer/build/StaticCS.CsSig.props b/src/CsSig/Analyzer/build/StaticCS.CsSig.props
index 41404c2..f639e36 100644
--- a/src/CsSig/Analyzer/build/StaticCS.CsSig.props
+++ b/src/CsSig/Analyzer/build/StaticCS.CsSig.props
@@ -8,6 +8,21 @@
       Include="**/*.cssig"
       Exclude="$(BaseIntermediateOutputPath)**/*.cssig;$(BaseOutputPath)**/*.cssig;bin/**/*.cssig;obj/**/*.cssig"
     />
+
+    <!--
+      Per-TFM signatures: a `<name>.<tfm>.cssig` file (e.g. PublicApi.net8.0.cssig) applies only
+      to that target framework. Drop every TFM-qualified file, then re-add the ones for the TFM
+      currently building, so multi-targeted projects can declare a distinct surface per TFM.
+    -->
+    <AdditionalFiles
+      Remove="**/*.net*.cssig;**/*.netstandard*.cssig;**/*.netcoreapp*.cssig"
+      Condition="'$(TargetFramework)' != ''"
+    />
+    <AdditionalFiles
+      Include="**/*.$(TargetFramework).cssig"
+      Exclude="$(BaseIntermediateOutputPath)**/*.cssig;$(BaseOutputPath)**/*.cssig;bin/**/*.cssig;obj/**/*.cssig"
+      Condition="'$(TargetFramework)' != ''"
+    />
   </ItemGroup>
 
   <!--