diff --git a/app/comp/df_cache.py b/app/comp/df_cache.py
index fb4c6cade..59dded343 100644
--- a/app/comp/df_cache.py
+++ b/app/comp/df_cache.py
@@ -27,6 +27,7 @@
 
 """caches pour tables APC
 """
+from flask import g
 
 from app.scodoc import sco_cache
 
@@ -47,3 +48,27 @@ class EvaluationsPoidsCache(sco_cache.ScoDocCache):
     """
 
     prefix = "EPC"
+
+    @classmethod
+    def invalidate_all(cls):
+        "delete all cached evaluations poids (in current dept)"
+        from app.models.formsemestre import FormSemestre
+        from app.models.moduleimpls import ModuleImpl
+
+        moduleimpl_ids = [
+            mi.id
+            for mi in ModuleImpl.query.join(FormSemestre).filter_by(
+                dept_id=g.scodoc_dept_id
+            )
+        ]
+        cls.delete_many(moduleimpl_ids)
+
+    @classmethod
+    def invalidate_sem(cls, formsemestre_id):
+        "delete cached evaluations poids for this formsemestre from cache"
+        from app.models.moduleimpls import ModuleImpl
+
+        moduleimpl_ids = [
+            mi.id for mi in ModuleImpl.query.filter_by(formsemestre_id=formsemestre_id)
+        ]
+        cls.delete_many(moduleimpl_ids)
diff --git a/app/scodoc/sco_cache.py b/app/scodoc/sco_cache.py
index 677dae6c9..102e4e433 100644
--- a/app/scodoc/sco_cache.py
+++ b/app/scodoc/sco_cache.py
@@ -274,6 +274,7 @@ def invalidate_formsemestre(  # was inval_cache(formsemestre_id=None, pdfonly=Fa
     """expire cache pour un semestre (ou tous ceux du département si formsemestre_id non spécifié).
     Si pdfonly, n'expire que les bulletins pdf cachés.
     """
+    from app.comp import df_cache
     from app.models.formsemestre import FormSemestre
     from app.scodoc import sco_cursus
 
@@ -315,12 +316,14 @@ def invalidate_formsemestre(  # was inval_cache(formsemestre_id=None, pdfonly=Fa
                     and fid in g.formsemestre_results_cache
                 ):
                     del g.formsemestre_results_cache[fid]
-
+            df_cache.EvaluationsPoidsCache.invalidate_sem(formsemestre_id)
         else:
             # optimization when we invalidate all evaluations:
             EvaluationCache.invalidate_all_sems()
+            df_cache.EvaluationsPoidsCache.invalidate_all()
             if hasattr(g, "formsemestre_results_cache"):
                 del g.formsemestre_results_cache
+
         SemInscriptionsCache.delete_many(formsemestre_ids)
         ResultatsSemestreCache.delete_many(formsemestre_ids)
         ValidationsSemestreCache.delete_many(formsemestre_ids)