diff --git a/src/io/mod.rs b/src/io/mod.rs
index 5f826c95f..e3d248857 100644
--- a/src/io/mod.rs
+++ b/src/io/mod.rs
@@ -757,8 +757,6 @@ pub fn load_bytes(name: &str, bytes: Vec<u8>) -> Result<CadDocument, String> {
             let mut doc = DwgReader::from_stream(Cursor::new(bytes))
                 .read()
                 .map_err(|e| e.to_string())?;
-            let version = doc.version;
-            fix_pre_r2000_layer_plot_flags(&mut doc, version);
             fix_viewport_status_flags(&mut doc);
             fix_current_style_names(&mut doc);
             Ok(doc)
@@ -1029,10 +1027,6 @@ fn finalize_loaded_outcome(
     mut outcome: codec::ReadOutcome,
 ) -> Result<codec::ReadOutcome, String> {
     let doc = &mut outcome.document;
-    if outcome.stats.source_format == Some(codec::SourceFormat::Dwg) {
-        let version = doc.version;
-        fix_pre_r2000_layer_plot_flags(doc, version);
-    }
     normalize_block_origins(doc);
     normalize_knotless_splines(doc);
     if outcome.stats.source_format == Some(codec::SourceFormat::Dxf) {
@@ -2394,31 +2388,6 @@ pub fn purge_corrupt_entities(doc: &mut CadDocument) -> usize {
     n
 }
 
-/// An R13 / R14 drawing cannot mark a layer as "don't plot" — the LAYER
-/// record only carries frozen, off, frozen-in-new-viewport and locked as four
-/// separate bits. The plot flag (and the lineweight, in the same packed
-/// bit-short) arrived with R2000, so the reader has no bit to read for the
-/// older versions and leaves the field at the `false` it starts from.
-///
-/// That default then marks every layer of such a drawing as "don't plot":
-/// display and plot visibility are separate flags, so the drawing looked right
-/// on screen while PLOT, the plot preview and QUICKPRINT all rendered a blank
-/// page. What the older format means by default is what a freshly created
-/// layer gets — `is_plottable: true` — so restore it here.
-fn fix_pre_r2000_layer_plot_flags(doc: &mut CadDocument, version: codec::types::DxfVersion) {
-    use codec::types::DxfVersion;
-    // AC1012 is R13 and AC1014 is R14, the two versions with the four-bit LAYER
-    // record. From AC1015 (R2000) on, the file's own flag is authoritative and
-    // is read, so nothing is touched there. `Unknown` is left alone too: a
-    // version that could not be identified is the wrong thing to reason from.
-    if !matches!(version, DxfVersion::AC1012 | DxfVersion::AC1014) {
-        return;
-    }
-    for layer in doc.layers.iter_mut() {
-        layer.is_plottable = true;
-    }
-}
-
 /// opencadcodec's ViewportStatusFlags::from_bits() maps bit 0 → is_on and bit 15 → locked,
 /// but the real DXF/DWG spec uses bit 15 (0x8000) → viewport on and bit 14 (0x4000) → locked.
 /// Files from AutoCAD and other tools always set bit 15 for active viewports, leaving bit 0
@@ -2943,8 +2912,13 @@ mod pre_r2000_layer_plot_tests {
         doc
     }
 
-    fn saved_path(version: DxfVersion) -> std::path::PathBuf {
-        std::env::temp_dir().join(format!("ocs_plotflag_{}.dwg", version.as_str()))
+    /// Tests run in parallel, so each gets its own file.
+    fn saved_path(test: &str, version: DxfVersion) -> std::path::PathBuf {
+        std::env::temp_dir().join(format!(
+            "ocs_plotflag_{test}_{}_{}.dwg",
+            version.as_str(),
+            std::process::id()
+        ))
     }
 
     /// The LAYER record only grew a plot flag in R2000. Reading an R14 drawing
@@ -2955,7 +2929,7 @@ mod pre_r2000_layer_plot_tests {
     #[test]
     fn an_r14_drawing_reads_back_with_every_layer_plottable() {
         let doc = drawing_with_layers();
-        let path = saved_path(DxfVersion::AC1014);
+        let path = saved_path("r14_bytes", DxfVersion::AC1014);
         save_as_version(&doc, &path, DxfVersion::AC1014).expect("save R14 DWG");
         let bytes = std::fs::read(&path).expect("read R14 DWG");
         let _ = std::fs::remove_file(&path);
@@ -2981,7 +2955,7 @@ mod pre_r2000_layer_plot_tests {
     #[test]
     fn an_r13_drawing_reads_back_with_every_layer_plottable() {
         let doc = drawing_with_layers();
-        let path = saved_path(DxfVersion::AC1012);
+        let path = saved_path("r13_path", DxfVersion::AC1012);
         save_as_version(&doc, &path, DxfVersion::AC1012).expect("save R13 DWG");
         let loaded = load_file(&path).expect("load R13 DWG");
         let _ = std::fs::remove_file(&path);
@@ -2997,7 +2971,7 @@ mod pre_r2000_layer_plot_tests {
     fn a_modern_drawing_keeps_the_plot_flag_it_stored() {
         let mut doc = drawing_with_layers();
         doc.layers.get_mut("FINE").unwrap().is_plottable = false;
-        let path = saved_path(DxfVersion::AC1032);
+        let path = saved_path("modern", DxfVersion::AC1032);
         save_as_version(&doc, &path, DxfVersion::AC1032).expect("save R2018 DWG");
         let loaded = load_file(&path).expect("load R2018 DWG");
         let _ = std::fs::remove_file(&path);
@@ -3025,7 +2999,7 @@ mod pre_r2000_layer_plot_tests {
             line.common.layer = layer.to_string();
             doc.add_entity(EntityType::Line(line)).expect("add line");
         }
-        let path = saved_path(DxfVersion::AC1014);
+        let path = saved_path("r14_wires", DxfVersion::AC1014);
         save_as_version(&doc, &path, DxfVersion::AC1014).expect("save R14 DWG");
         let bytes = std::fs::read(&path).expect("read R14 DWG");
         let _ = std::fs::remove_file(&path);