diff --git a/src/main/resources/alma/fix/item.fix b/src/main/resources/alma/fix/item.fix
index 8f39a3fb3..2b2273d72 100644
--- a/src/main/resources/alma/fix/item.fix
+++ b/src/main/resources/alma/fix/item.fix
@@ -125,3 +125,21 @@ do list(path: "hasItem[]","var":"$i")
     add_field("$i.inCollection[].1.label","Bibliotheken ohne zentrale Katalogisierung (IZ Bridge)")
   end
 end
+
+set_array("@callNumberRvk[]")
+do list(path:"hasItem[]","var":"$i")
+  if any_match("$i.callNumber","([A-Z]{2} \\d{3,6})(\\.\\d*)?( [A-Z]\\d+)+([\\.\\d\\-\\(\\)+]*)?")
+    copy_field("$i.callNumber","@callNumberRvk[].$append")
+  end
+end
+
+replace_all("@callNumberRvk[].*","([A-Z][A-Z] \\d{3,6}) .*","$1")
+
+do list(path:"@callNumberRvk[]","var":"$i")
+  copy_field("$i","subject[].$append.notation")
+  set_array("subject[].$last.type[]","Concept")
+  add_field("subject[].$last.source.label","RVK (Regensburger Verbundklassifikation)")
+  add_field("subject[].$last.source.id","https://d-nb.info/gnd/4449787-8")
+end
+
+uniq("subject[]")
diff --git a/src/test/resources/alma-fix/990014830510206441.json b/src/test/resources/alma-fix/990014830510206441.json
index df82560a9..3ad5b2575 100644
--- a/src/test/resources/alma-fix/990014830510206441.json
+++ b/src/test/resources/alma-fix/990014830510206441.json
@@ -100,6 +100,13 @@
       "dateOfDeath" : "1977",
       "altLabel" : [ "Chaplin, Charles S.", "Spencer Chaplin, Charles", "Chaplin, Charly", "Tsaplin, Tsarl Spenser", "Sa-plin, Sác-li", "Cāplin, Cārlī", "Čaplin, Č'arlz", "Chaplin, Charles Spencer", "Chaplin, Charles", "Čaplin, Čarl'z Spenser", "Spencer-Chaplin, Charles", "Чаплин, Чарльз", "Zhuobielin", "Sarlō", "Charlot", "Sac-lô" ]
     } ]
+  }, {
+    "notation" : "AP 51081",
+    "type" : [ "Concept" ],
+    "source" : {
+      "label" : "RVK (Regensburger Verbundklassifikation)",
+      "id" : "https://d-nb.info/gnd/4449787-8"
+    }
   } ],
   "subjectslabels" : [ "Chaplin, Charlie" ],
   "hasItem" : [ {
diff --git a/src/test/resources/alma-fix/990058434730206441.json b/src/test/resources/alma-fix/990058434730206441.json
index ffddba455..3ccdbf5bd 100644
--- a/src/test/resources/alma-fix/990058434730206441.json
+++ b/src/test/resources/alma-fix/990058434730206441.json
@@ -155,6 +155,13 @@
       "dateOfDeath" : "0039",
       "altLabel" : [ "Herodes Antipatros", "Herodes, Antipas" ]
     } ]
+  }, {
+    "notation" : "BC 8740",
+    "type" : [ "Concept" ],
+    "source" : {
+      "label" : "RVK (Regensburger Verbundklassifikation)",
+      "id" : "https://d-nb.info/gnd/4449787-8"
+    }
   } ],
   "subjectslabels" : [ "Herodes <Judäa, König, I.>", "Makkabäer", "Herrschaftssystem", "Neues Testament / Zeithintergrund", "Herodes Antipas, Galiläa, Tetrarch" ],
   "hasItem" : [ {
diff --git a/src/test/resources/alma-fix/990075429930206441.json b/src/test/resources/alma-fix/990075429930206441.json
index a21fd18f9..e9187bc22 100644
--- a/src/test/resources/alma-fix/990075429930206441.json
+++ b/src/test/resources/alma-fix/990075429930206441.json
@@ -87,6 +87,14 @@
     "label" : "Deutsch"
   } ],
   "extent" : "64 S.",
+  "subject" : [ {
+    "notation" : "BO 4075",
+    "type" : [ "Concept" ],
+    "source" : {
+      "label" : "RVK (Regensburger Verbundklassifikation)",
+      "id" : "https://d-nb.info/gnd/4449787-8"
+    }
+  } ],
   "hasItem" : [ {
     "label" : "lobid Bestandsressource",
     "type" : [ "Item", "PhysicalObject" ],