diff --git a/time-machine/src/main/kotlin/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplier.kt b/time-machine/src/main/kotlin/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplier.kt
index f4c547d0d..9ce72ac5a 100644
--- a/time-machine/src/main/kotlin/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplier.kt
+++ b/time-machine/src/main/kotlin/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplier.kt
@@ -12,8 +12,10 @@ fun applyModification(amendingLaw: Document, targetLaw: Document): Document {
   val modification = getFirstModification(amendingLaw)
   requireNotNull(modification) { "Amending law does not include any modification" }
 
-  val eId = getReferenceEid(modification)
-  requireNotNull(eId) { "Modification has no target reference" }
+  val eli = findHrefInModification(modification)
+  requireNotNull(eli) { "Could not find href in modification" }
+
+  val eId = extractLokaleKomponente(eli)
 
   val elementToModify = findElementToModify(eId, amendedLaw)
   requireNotNull(elementToModify) { "Could not find element to modify with eId: '$eId'" }
@@ -34,10 +36,10 @@ fun applyModification(amendingLaw: Document, targetLaw: Document): Document {
 
 fun getFirstModification(amendingLaw: Document) = getNode("//*[local-name()='mod']", amendingLaw)
 
-fun getReferenceEid(modification: Node): String? {
-  val href = getNode("//*[local-name()='ref']/@href", modification)?.nodeValue
-  return href?.split("/")?.takeLast(2)?.get(0)
-}
+fun findHrefInModification(modification: Node): String? =
+    getNode("//*[local-name()='ref']/@href", modification)?.nodeValue
+
+fun extractLokaleKomponente(eli: String) = eli.split("/").takeLast(2)[0]
 
 fun findElementToModify(eId: String, amendedLaw: Document) = getNode("//*[@eId='$eId']", amendedLaw)
 
diff --git a/time-machine/src/test/kotlin/unit/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplierTest.kt b/time-machine/src/test/kotlin/unit/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplierTest.kt
index c19b04473..4bbf51907 100644
--- a/time-machine/src/test/kotlin/unit/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplierTest.kt
+++ b/time-machine/src/test/kotlin/unit/de/bund/digitalservice/ris/norms/timemachine/core/ModificationApplierTest.kt
@@ -62,20 +62,6 @@ class ModificationApplierTest {
         .hasMessage("Amending law does not include any modification")
   }
 
-  @Test
-  fun `it throws an exception if the modification does not include a reference with an eId`() {
-    val amendingLaw =
-        """
-              <akn:body>
-                <akn:mod>Change paragraph 2</akn:mod>
-              </akn:body>
-            """
-
-    assertThatThrownBy { applyModification(amendingLaw.asXml(), anyTargetLaw.asXml()) }
-        .isInstanceOf(IllegalArgumentException::class.java)
-        .hasMessage("Modification has no target reference")
-  }
-
   @Test
   fun `it throws an exception if there is no element with the eId to modify`() {
     val amendingLaw =
@@ -98,6 +84,63 @@ class ModificationApplierTest {
         .isInstanceOf(IllegalArgumentException::class.java)
         .hasMessage("Could not find element to modify with eId: 'none'")
   }
+
+  @Test
+  fun `it throws an exception if the text to be replaced can't be found`() {
+    val amendingLaw =
+        """
+      <akn:body>
+        <akn:mod>
+            In <akn:ref href="any">paragraph 2</akn:ref> .
+        </akn:mod>
+      </akn:body>
+    """
+
+    assertThatThrownBy { applyModification(amendingLaw.asXml(), anyTargetLaw.asXml()) }
+        .isInstanceOf(IllegalArgumentException::class.java)
+        .hasMessage("Could not find text that should be replaced")
+  }
+
+  @Test
+  fun `it throws an exception if the replacement text can't be found`() {
+    val amendingLaw =
+        """
+      <akn:body>
+        <akn:mod>
+            In <akn:ref href="any">paragraph 2</akn:ref> replace <akn:quotedText>old</akn:quotedText> with.
+        </akn:mod>
+      </akn:body>
+    """
+
+    assertThatThrownBy { applyModification(amendingLaw.asXml(), anyTargetLaw.asXml()) }
+        .isInstanceOf(IllegalArgumentException::class.java)
+        .hasMessage("Could not find replacement text")
+  }
+
+  @Test
+  fun `it throws an exception if no href is found in modification`() {
+    val amendingLaw =
+        """
+      <akn:body>
+        <akn:mod>
+        </akn:mod>
+      </akn:body>
+    """
+
+    assertThatThrownBy { applyModification(amendingLaw.asXml(), anyTargetLaw.asXml()) }
+        .isInstanceOf(IllegalArgumentException::class.java)
+        .hasMessage("Could not find href in modification")
+  }
+
+  @Test
+  fun `it gets the lokale Komponente from an ELI`() {
+    val eli =
+        "eli/bund/bgbl-1/1964/s593/1964-08-05/1/deu/regelungstext-1/para-20_abs-1_untergl-1_listenelem-2_inhalt-1_text-1/9-34.xml"
+
+    val result = extractLokaleKomponente(eli)
+
+    assertThat(result).isEqualTo("para-20_abs-1_untergl-1_listenelem-2_inhalt-1_text-1")
+  }
 }
 
 private const val anyAmendingLaw =