diff --git a/src/main/java/edu/ie3/simona/api/ExtLinkInterface.java b/src/main/java/edu/ie3/simona/api/ExtLinkInterface.java
index 0761008a..07753b5e 100644
--- a/src/main/java/edu/ie3/simona/api/ExtLinkInterface.java
+++ b/src/main/java/edu/ie3/simona/api/ExtLinkInterface.java
@@ -6,8 +6,8 @@
 
 package edu.ie3.simona.api;
 
+import edu.ie3.simona.api.data.ExtSimAdapterData;
 import edu.ie3.simona.api.exceptions.NoExtSimulationException;
-import edu.ie3.simona.api.simulation.ExtSimAdapterData;
 import edu.ie3.simona.api.simulation.ExtSimulation;
 
 /**
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ExtSimAdapterData.java b/src/main/java/edu/ie3/simona/api/data/ExtSimAdapterData.java
similarity index 91%
rename from src/main/java/edu/ie3/simona/api/simulation/ExtSimAdapterData.java
rename to src/main/java/edu/ie3/simona/api/data/ExtSimAdapterData.java
index 59f81b1e..175ff38b 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ExtSimAdapterData.java
+++ b/src/main/java/edu/ie3/simona/api/data/ExtSimAdapterData.java
@@ -4,10 +4,10 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation;
+package edu.ie3.simona.api.data;
 
-import edu.ie3.simona.api.simulation.ontology.ControlMessageToExt;
-import edu.ie3.simona.api.simulation.ontology.ControlResponseMessageFromExt;
+import edu.ie3.simona.api.ontology.simulation.ControlMessageToExt;
+import edu.ie3.simona.api.ontology.simulation.ControlResponseMessageFromExt;
 import java.util.concurrent.LinkedBlockingQueue;
 import org.apache.pekko.actor.typed.ActorRef;
 
diff --git a/src/main/java/edu/ie3/simona/api/data/container/ExtInputDataContainer.java b/src/main/java/edu/ie3/simona/api/data/container/ExtInputDataContainer.java
new file mode 100644
index 00000000..dc14924d
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/data/container/ExtInputDataContainer.java
@@ -0,0 +1,120 @@
+/*
+ * © 2024. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.data.container;
+
+import edu.ie3.datamodel.models.value.PValue;
+import edu.ie3.datamodel.models.value.Value;
+import edu.ie3.simona.api.data.model.em.FlexOptionRequestValue;
+import edu.ie3.simona.api.data.model.em.FlexOptions;
+import java.util.*;
+
+/** Contains all inputs for SIMONA for a certain tick */
+public final class ExtInputDataContainer implements ExtDataContainer {
+
+  /** The tick, the input data is meant for */
+  private final long tick;
+
+  /** The next tick, when data will be provided, if available */
+  private final Optional<Long> maybeNextTick;
+
+  // primary map
+  /** Map external id to primary input value for SIMONA */
+  private final Map<UUID, Value> primaryData = new HashMap<>();
+
+  // em maps
+  private final Map<UUID, FlexOptionRequestValue> flexRequests = new HashMap<>();
+  private final Map<UUID, List<FlexOptions>> flexOptions = new HashMap<>();
+  private final Map<UUID, PValue> setPoints = new HashMap<>();
+
+  /**
+   * Container class for input data for SIMONA which can be read by SimonaAPI
+   *
+   * @param tick The tick, the input data is meant for
+   * @param nextTick tick, when the next data will be provided
+   */
+  public ExtInputDataContainer(long tick, long nextTick) {
+    this.tick = tick;
+    this.maybeNextTick = Optional.of(nextTick);
+  }
+
+  public ExtInputDataContainer(long tick) {
+    this.tick = tick;
+    this.maybeNextTick = Optional.empty();
+  }
+
+  @Override
+  public boolean isEmpty() {
+    return primaryData.isEmpty()
+        && flexRequests.isEmpty()
+        && flexOptions.isEmpty()
+        && setPoints.isEmpty();
+  }
+
+  public long getTick() {
+    return tick;
+  }
+
+  public Optional<Long> getMaybeNextTick() {
+    return maybeNextTick;
+  }
+
+  // add data
+  public void addPrimaryValue(UUID id, Value value) {
+    primaryData.put(id, value);
+  }
+
+  public void addRequest(UUID requester, List<UUID> emEntities) {
+    flexRequests.put(requester, new FlexOptionRequestValue(requester, emEntities));
+  }
+
+  public void addFlexOptions(UUID id, List<FlexOptions> flexOption) {
+    if (!flexOptions.containsKey(id)) {
+      List<FlexOptions> flexOptionValues = new ArrayList<>(flexOption);
+      flexOptions.put(id, flexOptionValues);
+    } else {
+      flexOptions.get(id).addAll(flexOption);
+    }
+  }
+
+  public void addSetPoint(UUID id, PValue setPoint) {
+    setPoints.put(id, setPoint);
+  }
+
+  public Map<UUID, Value> extractPrimaryData() {
+    return copyAndClear(primaryData);
+  }
+
+  // extract and delete data
+  public Map<UUID, FlexOptionRequestValue> extractFlexRequests() {
+    return copyAndClear(flexRequests);
+  }
+
+  public Map<UUID, List<FlexOptions>> extractFlexOptions() {
+    return copyAndClear(flexOptions);
+  }
+
+  public Map<UUID, PValue> extractSetPoints() {
+    return copyAndClear(setPoints);
+  }
+
+  // data to string
+  public String primaryDataString() {
+    return primaryData.toString();
+  }
+
+  public String flexRequestsString() {
+    return flexRequests.toString();
+  }
+
+  public String flexOptionsString() {
+    return flexOptions.toString();
+  }
+
+  public String setPointsString() {
+    return setPoints.toString();
+  }
+}
diff --git a/src/main/java/edu/ie3/simona/api/data/model/em/EmSetPointResult.java b/src/main/java/edu/ie3/simona/api/data/model/em/EmSetPointResult.java
new file mode 100644
index 00000000..cbe72fff
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/data/model/em/EmSetPointResult.java
@@ -0,0 +1,40 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.data.model.em;
+
+import edu.ie3.datamodel.models.result.ResultEntity;
+import edu.ie3.datamodel.models.value.PValue;
+import java.time.ZonedDateTime;
+import java.util.Optional;
+import java.util.UUID;
+
+/** Em set point result. */
+public class EmSetPointResult extends ResultEntity {
+
+  private final PValue setPoint;
+
+  public EmSetPointResult(ZonedDateTime time, UUID inputModel, PValue setPoint) {
+    super(time, inputModel);
+    this.setPoint = setPoint;
+  }
+
+  public Optional<PValue> getSetPoint() {
+    return Optional.ofNullable(setPoint);
+  }
+
+  @Override
+  public String toString() {
+    return "EmSetPointResult{"
+        + "time="
+        + getTime()
+        + ", inputModel="
+        + getInputModel()
+        + ", setPoint="
+        + getSetPoint()
+        + '}';
+  }
+}
diff --git a/src/main/java/edu/ie3/simona/api/data/model/em/FlexOptionRequestValue.java b/src/main/java/edu/ie3/simona/api/data/model/em/FlexOptionRequestValue.java
new file mode 100644
index 00000000..ec9a9a3a
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/data/model/em/FlexOptionRequestValue.java
@@ -0,0 +1,13 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.data.model.em;
+
+import edu.ie3.datamodel.models.value.Value;
+import java.util.List;
+import java.util.UUID;
+
+public record FlexOptionRequestValue(UUID requester, List<UUID> emEntities) implements Value {}
diff --git a/src/main/java/edu/ie3/simona/api/data/model/em/FlexOptionValue.java b/src/main/java/edu/ie3/simona/api/data/model/em/FlexOptionValue.java
new file mode 100644
index 00000000..c32cc06b
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/data/model/em/FlexOptionValue.java
@@ -0,0 +1,13 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.data.model.em;
+
+import edu.ie3.datamodel.models.value.Value;
+import java.util.Map;
+import java.util.UUID;
+
+public record FlexOptionValue(Map<UUID, FlexOptions> flexOptions) implements Value {}
diff --git a/src/main/java/edu/ie3/simona/api/data/model/em/FlexRequestResult.java b/src/main/java/edu/ie3/simona/api/data/model/em/FlexRequestResult.java
new file mode 100644
index 00000000..7843e816
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/data/model/em/FlexRequestResult.java
@@ -0,0 +1,24 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.data.model.em;
+
+import edu.ie3.datamodel.models.result.ResultEntity;
+import java.time.ZonedDateTime;
+import java.util.UUID;
+
+public class FlexRequestResult extends ResultEntity {
+
+  /**
+   * Standard constructor which includes auto generation of the resulting output models uuid.
+   *
+   * @param time date and time when the result is produced
+   * @param inputModel uuid of the input model that produces the result
+   */
+  public FlexRequestResult(ZonedDateTime time, UUID inputModel) {
+    super(time, inputModel);
+  }
+}
diff --git a/src/main/java/edu/ie3/simona/api/data/model/em/NoSetPointValue.java b/src/main/java/edu/ie3/simona/api/data/model/em/NoSetPointValue.java
new file mode 100644
index 00000000..62d94c18
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/data/model/em/NoSetPointValue.java
@@ -0,0 +1,17 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.data.model.em;
+
+import edu.ie3.datamodel.models.value.PValue;
+import javax.measure.quantity.Power;
+import tech.units.indriya.ComparableQuantity;
+
+public class NoSetPointValue extends PValue {
+  public NoSetPointValue(ComparableQuantity<Power> p) {
+    super(p);
+  }
+}
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/model/EvModel.java b/src/main/java/edu/ie3/simona/api/data/model/ev/EvModel.java
similarity index 96%
rename from src/main/java/edu/ie3/simona/api/data/ev/model/EvModel.java
rename to src/main/java/edu/ie3/simona/api/data/model/ev/EvModel.java
index 2ea3082d..04c1fd05 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/model/EvModel.java
+++ b/src/main/java/edu/ie3/simona/api/data/model/ev/EvModel.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.model;
+package edu.ie3.simona.api.data.model.ev;
 
 import java.util.UUID;
 import javax.measure.quantity.Energy;
diff --git a/src/main/java/edu/ie3/simona/api/mapping/DataType.java b/src/main/java/edu/ie3/simona/api/mapping/DataType.java
index ea6d2d4a..42794233 100644
--- a/src/main/java/edu/ie3/simona/api/mapping/DataType.java
+++ b/src/main/java/edu/ie3/simona/api/mapping/DataType.java
@@ -11,6 +11,8 @@
 public enum DataType {
   EXT_PRIMARY_INPUT("primary_input"),
   EXT_EM_INPUT("em_input"),
+  EXT_EM_COMMUNICATION("em_communication"),
+  EXT_EM_OPTIMIZER("em_optimizer"),
   EXT_GRID_RESULT("grid_result"),
   EXT_PARTICIPANT_RESULT("participant_result"),
   EXT_FLEX_OPTIONS_RESULT("flex_options_result");
diff --git a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityEntry.java b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityEntry.java
similarity index 100%
rename from src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityEntry.java
rename to src/main/java/edu/ie3/simona/api/mapping/ExtEntityEntry.java
diff --git a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityFactory.java b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityFactory.java
similarity index 97%
rename from src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityFactory.java
rename to src/main/java/edu/ie3/simona/api/mapping/ExtEntityFactory.java
index 4b79cca4..878def37 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityFactory.java
+++ b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityFactory.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.mapping;
+package edu.ie3.simona.api.mapping;
 
 import edu.ie3.datamodel.exceptions.FactoryException;
 import edu.ie3.datamodel.exceptions.ParsingException;
diff --git a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityMapping.java b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityMapping.java
similarity index 97%
rename from src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityMapping.java
rename to src/main/java/edu/ie3/simona/api/mapping/ExtEntityMapping.java
index 6976be08..c4cc7ffc 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityMapping.java
+++ b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityMapping.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.mapping;
+package edu.ie3.simona.api.mapping;
 
 import edu.ie3.simona.api.mapping.DataType;
 import java.util.Collections;
diff --git a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingSource.java b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityMappingSource.java
similarity index 98%
rename from src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingSource.java
rename to src/main/java/edu/ie3/simona/api/mapping/ExtEntityMappingSource.java
index 1d24d7ff..f540f1c9 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingSource.java
+++ b/src/main/java/edu/ie3/simona/api/mapping/ExtEntityMappingSource.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.mapping;
+package edu.ie3.simona.api.mapping;
 
 import edu.ie3.datamodel.exceptions.SourceException;
 import edu.ie3.datamodel.io.factory.EntityData;
diff --git a/src/main/java/edu/ie3/simona/api/data/ontology/DataMessageFromExt.java b/src/main/java/edu/ie3/simona/api/ontology/DataMessageFromExt.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/data/ontology/DataMessageFromExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/DataMessageFromExt.java
index 66a79ed9..14a0a5f5 100644
--- a/src/main/java/edu/ie3/simona/api/data/ontology/DataMessageFromExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/DataMessageFromExt.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ontology;
+package edu.ie3.simona.api.ontology;
 
 /** Data related messages that are sent from the external simulation to SIMONA */
 public interface DataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/ontology/DataResponseMessageToExt.java b/src/main/java/edu/ie3/simona/api/ontology/DataResponseMessageToExt.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/data/ontology/DataResponseMessageToExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/DataResponseMessageToExt.java
index 2eb2f29c..a191eaf2 100644
--- a/src/main/java/edu/ie3/simona/api/data/ontology/DataResponseMessageToExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/DataResponseMessageToExt.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ontology;
+package edu.ie3.simona.api.ontology;
 
 /** Data related messages that are sent from SIMONA to the external simulation */
 public interface DataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/ontology/ScheduleDataServiceMessage.java b/src/main/java/edu/ie3/simona/api/ontology/ScheduleDataServiceMessage.java
similarity index 77%
rename from src/main/java/edu/ie3/simona/api/data/ontology/ScheduleDataServiceMessage.java
rename to src/main/java/edu/ie3/simona/api/ontology/ScheduleDataServiceMessage.java
index 029b840d..4cc0fc98 100644
--- a/src/main/java/edu/ie3/simona/api/data/ontology/ScheduleDataServiceMessage.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ScheduleDataServiceMessage.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ontology;
+package edu.ie3.simona.api.ontology;
 
-import edu.ie3.simona.api.simulation.ontology.ControlResponseMessageFromExt;
+import edu.ie3.simona.api.ontology.simulation.ControlResponseMessageFromExt;
 import org.apache.pekko.actor.typed.ActorRef;
 
 public record ScheduleDataServiceMessage(ActorRef<DataMessageFromExt> dataService)
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/EmCompletion.java b/src/main/java/edu/ie3/simona/api/ontology/em/EmCompletion.java
new file mode 100644
index 00000000..100de1bd
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/EmCompletion.java
@@ -0,0 +1,9 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+public record EmCompletion() implements EmDataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/em/ontology/EmDataMessageFromExt.java b/src/main/java/edu/ie3/simona/api/ontology/em/EmDataMessageFromExt.java
similarity index 76%
rename from src/main/java/edu/ie3/simona/api/data/em/ontology/EmDataMessageFromExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/em/EmDataMessageFromExt.java
index a5ea688c..936e43a2 100644
--- a/src/main/java/edu/ie3/simona/api/data/em/ontology/EmDataMessageFromExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/EmDataMessageFromExt.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.em.ontology;
+package edu.ie3.simona.api.ontology.em;
 
-import edu.ie3.simona.api.data.ontology.DataMessageFromExt;
+import edu.ie3.simona.api.ontology.DataMessageFromExt;
 
 /** Messages that are sent from an external data simulation which provides em data to SIMONA. */
 public interface EmDataMessageFromExt extends DataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/em/ontology/EmDataResponseMessageToExt.java b/src/main/java/edu/ie3/simona/api/ontology/em/EmDataResponseMessageToExt.java
similarity index 100%
rename from src/main/java/edu/ie3/simona/api/data/em/ontology/EmDataResponseMessageToExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/em/EmDataResponseMessageToExt.java
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/EmSetPointDataResponse.java b/src/main/java/edu/ie3/simona/api/ontology/em/EmSetPointDataResponse.java
new file mode 100644
index 00000000..c7a6c6e5
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/EmSetPointDataResponse.java
@@ -0,0 +1,15 @@
+/*
+ * © 2024. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import edu.ie3.simona.api.data.model.em.EmSetPointResult;
+import java.util.Map;
+import java.util.UUID;
+
+/** Message that provides em data (set points) to an external simulation. */
+public record EmSetPointDataResponse(Map<UUID, EmSetPointResult> emData)
+    implements EmDataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/FlexOptionsResponse.java b/src/main/java/edu/ie3/simona/api/ontology/em/FlexOptionsResponse.java
new file mode 100644
index 00000000..6fe7bdea
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/FlexOptionsResponse.java
@@ -0,0 +1,15 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import edu.ie3.datamodel.models.result.system.FlexOptionsResult;
+import java.util.Map;
+import java.util.UUID;
+
+/** Message that provides em data (flexibility options) to an external simulation. */
+public record FlexOptionsResponse(Map<UUID, FlexOptionsResult> flexOptions)
+    implements EmDataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/FlexRequestResponse.java b/src/main/java/edu/ie3/simona/api/ontology/em/FlexRequestResponse.java
new file mode 100644
index 00000000..69f8a1c4
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/FlexRequestResponse.java
@@ -0,0 +1,15 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import edu.ie3.simona.api.data.model.em.FlexRequestResult;
+import java.util.Map;
+import java.util.UUID;
+
+/** Message that provides em data (flexibility requests) to an external simulation. */
+public record FlexRequestResponse(Map<UUID, FlexRequestResult> flexRequests)
+    implements EmDataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/ProvideEmFlexOptionData.java b/src/main/java/edu/ie3/simona/api/ontology/em/ProvideEmFlexOptionData.java
new file mode 100644
index 00000000..3d8d0e53
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/ProvideEmFlexOptionData.java
@@ -0,0 +1,18 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import edu.ie3.simona.api.data.model.em.FlexOptions;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.UUID;
+
+/** Message that provides em data (flexibility options) from an external simulation. */
+public record ProvideEmFlexOptionData(
+    long tick, Map<UUID, List<FlexOptions>> flexOptions, Optional<Long> maybeNextTick)
+    implements EmDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/em/ontology/ProvideEmSetPointData.java b/src/main/java/edu/ie3/simona/api/ontology/em/ProvideEmSetPointData.java
similarity index 92%
rename from src/main/java/edu/ie3/simona/api/data/em/ontology/ProvideEmSetPointData.java
rename to src/main/java/edu/ie3/simona/api/ontology/em/ProvideEmSetPointData.java
index 3f2bb40b..330da4bf 100644
--- a/src/main/java/edu/ie3/simona/api/data/em/ontology/ProvideEmSetPointData.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/ProvideEmSetPointData.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.em.ontology;
+package edu.ie3.simona.api.ontology.em;
 
 import edu.ie3.simona.api.data.model.em.EmSetPoint;
 import java.util.Map;
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/ProvideFlexRequestData.java b/src/main/java/edu/ie3/simona/api/ontology/em/ProvideFlexRequestData.java
new file mode 100644
index 00000000..119b8e43
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/ProvideFlexRequestData.java
@@ -0,0 +1,17 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.UUID;
+
+/** Message that provides em data (flex requests) from an external simulation. */
+public record ProvideFlexRequestData(
+    long tick, Map<UUID, List<UUID>> flexRequests, Optional<Long> maybeNextTick)
+    implements EmDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/RequestControlledEmFlexResults.java b/src/main/java/edu/ie3/simona/api/ontology/em/RequestControlledEmFlexResults.java
new file mode 100644
index 00000000..e701b391
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/RequestControlledEmFlexResults.java
@@ -0,0 +1,14 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import java.util.Set;
+import java.util.UUID;
+
+/** Request em set flex options from SIMONA via external simulation. */
+public record RequestControlledEmFlexResults(Set<UUID> emEntities)
+    implements EmDataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmCompletion.java b/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmCompletion.java
new file mode 100644
index 00000000..209d8e20
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmCompletion.java
@@ -0,0 +1,9 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+public record RequestEmCompletion(long tick) implements EmDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmFlexResults.java b/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmFlexResults.java
new file mode 100644
index 00000000..b90a7a83
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmFlexResults.java
@@ -0,0 +1,15 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+/** Request em set points from SIMONA in the given tick. */
+public record RequestEmFlexResults(long tick, Map<UUID, List<UUID>> emEntities)
+    implements EmDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmSetPoints.java b/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmSetPoints.java
new file mode 100644
index 00000000..b143c838
--- /dev/null
+++ b/src/main/java/edu/ie3/simona/api/ontology/em/RequestEmSetPoints.java
@@ -0,0 +1,14 @@
+/*
+ * © 2025. TU Dortmund University,
+ * Institute of Energy Systems, Energy Efficiency and Energy Economics,
+ * Research group Distribution grid planning and operation
+ */
+
+package edu.ie3.simona.api.ontology.em;
+
+import java.util.List;
+import java.util.UUID;
+
+/** Request em set points from SIMONA in the given tick. */
+public record RequestEmSetPoints(long tick, List<UUID> emEntities)
+    implements EmDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/EvDataMessageFromExt.java b/src/main/java/edu/ie3/simona/api/ontology/ev/EvDataMessageFromExt.java
similarity index 70%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/EvDataMessageFromExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/EvDataMessageFromExt.java
index 2eb04bdf..a3c71012 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/EvDataMessageFromExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/EvDataMessageFromExt.java
@@ -4,8 +4,8 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
-import edu.ie3.simona.api.data.ontology.DataMessageFromExt;
+import edu.ie3.simona.api.ontology.DataMessageFromExt;
 
 public interface EvDataMessageFromExt extends DataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/EvDataResponseMessageToExt.java b/src/main/java/edu/ie3/simona/api/ontology/ev/EvDataResponseMessageToExt.java
similarity index 74%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/EvDataResponseMessageToExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/EvDataResponseMessageToExt.java
index 59a49503..b5ed6c4e 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/EvDataResponseMessageToExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/EvDataResponseMessageToExt.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
-import edu.ie3.simona.api.data.ontology.DataResponseMessageToExt;
+import edu.ie3.simona.api.ontology.DataResponseMessageToExt;
 
 /** Messages that are sent from SIMONA to the external ev simulation */
 public interface EvDataResponseMessageToExt extends DataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideArrivingEvs.java b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideArrivingEvs.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideArrivingEvs.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/ProvideArrivingEvs.java
index da9b5724..8ec7e1ff 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideArrivingEvs.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideArrivingEvs.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
-import edu.ie3.simona.api.data.ev.model.EvModel;
+import edu.ie3.simona.api.data.model.ev.EvModel;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideCurrentPrices.java b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideCurrentPrices.java
similarity index 92%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideCurrentPrices.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/ProvideCurrentPrices.java
index 9688d621..24bfe58a 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideCurrentPrices.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideCurrentPrices.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
 import java.util.HashMap;
 import java.util.Map;
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideDepartingEvs.java b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideDepartingEvs.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideDepartingEvs.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/ProvideDepartingEvs.java
index 4f1e5637..df71882b 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideDepartingEvs.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideDepartingEvs.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
-import edu.ie3.simona.api.data.ev.model.EvModel;
+import edu.ie3.simona.api.data.model.ev.EvModel;
 import java.util.ArrayList;
 import java.util.List;
 
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideEvcsFreeLots.java b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideEvcsFreeLots.java
similarity index 93%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideEvcsFreeLots.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/ProvideEvcsFreeLots.java
index 29264570..b2e27129 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/ProvideEvcsFreeLots.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/ProvideEvcsFreeLots.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
 import java.util.HashMap;
 import java.util.Map;
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestCurrentPrices.java b/src/main/java/edu/ie3/simona/api/ontology/ev/RequestCurrentPrices.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestCurrentPrices.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/RequestCurrentPrices.java
index f16adfb9..6a158446 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestCurrentPrices.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/RequestCurrentPrices.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
 /** Request current charging prices per charging station. */
 public record RequestCurrentPrices() implements EvDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestDepartingEvs.java b/src/main/java/edu/ie3/simona/api/ontology/ev/RequestDepartingEvs.java
similarity index 92%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestDepartingEvs.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/RequestDepartingEvs.java
index 7aabcb06..398277a4 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestDepartingEvs.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/RequestDepartingEvs.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
 import java.util.List;
 import java.util.Map;
diff --git a/src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestEvcsFreeLots.java b/src/main/java/edu/ie3/simona/api/ontology/ev/RequestEvcsFreeLots.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestEvcsFreeLots.java
rename to src/main/java/edu/ie3/simona/api/ontology/ev/RequestEvcsFreeLots.java
index b394f5b0..57d5f67b 100644
--- a/src/main/java/edu/ie3/simona/api/data/ev/ontology/RequestEvcsFreeLots.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/ev/RequestEvcsFreeLots.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.ev.ontology;
+package edu.ie3.simona.api.ontology.ev;
 
 /** Request the number of free lots per charging station from SIMONA */
 public record RequestEvcsFreeLots() implements EvDataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/primarydata/ontology/PrimaryDataMessageFromExt.java b/src/main/java/edu/ie3/simona/api/ontology/primary/PrimaryDataMessageFromExt.java
similarity index 74%
rename from src/main/java/edu/ie3/simona/api/data/primarydata/ontology/PrimaryDataMessageFromExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/primary/PrimaryDataMessageFromExt.java
index e7eb7ae6..529cb275 100644
--- a/src/main/java/edu/ie3/simona/api/data/primarydata/ontology/PrimaryDataMessageFromExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/primary/PrimaryDataMessageFromExt.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.primarydata.ontology;
+package edu.ie3.simona.api.ontology.primary;
 
-import edu.ie3.simona.api.data.ontology.DataMessageFromExt;
+import edu.ie3.simona.api.ontology.DataMessageFromExt;
 
 /** Messages that are sent from an external primary data simulation to SIMONA */
 public interface PrimaryDataMessageFromExt extends DataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/primarydata/ontology/ProvidePrimaryData.java b/src/main/java/edu/ie3/simona/api/ontology/primary/ProvidePrimaryData.java
similarity index 90%
rename from src/main/java/edu/ie3/simona/api/data/primarydata/ontology/ProvidePrimaryData.java
rename to src/main/java/edu/ie3/simona/api/ontology/primary/ProvidePrimaryData.java
index 2c316323..9b3382df 100644
--- a/src/main/java/edu/ie3/simona/api/data/primarydata/ontology/ProvidePrimaryData.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/primary/ProvidePrimaryData.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.primarydata.ontology;
+package edu.ie3.simona.api.ontology.primary;
 
 import edu.ie3.datamodel.models.value.Value;
 import java.util.Map;
diff --git a/src/main/java/edu/ie3/simona/api/data/results/ontology/ProvideResultEntities.java b/src/main/java/edu/ie3/simona/api/ontology/result/ProvideResultEntities.java
similarity index 92%
rename from src/main/java/edu/ie3/simona/api/data/results/ontology/ProvideResultEntities.java
rename to src/main/java/edu/ie3/simona/api/ontology/result/ProvideResultEntities.java
index 0c0d003f..dc1ad242 100644
--- a/src/main/java/edu/ie3/simona/api/data/results/ontology/ProvideResultEntities.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/result/ProvideResultEntities.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.results.ontology;
+package edu.ie3.simona.api.ontology.result;
 
 import edu.ie3.datamodel.models.result.ResultEntity;
 import java.util.List;
diff --git a/src/main/java/edu/ie3/simona/api/data/results/ontology/RequestResultEntities.java b/src/main/java/edu/ie3/simona/api/ontology/result/RequestResultEntities.java
similarity index 81%
rename from src/main/java/edu/ie3/simona/api/data/results/ontology/RequestResultEntities.java
rename to src/main/java/edu/ie3/simona/api/ontology/result/RequestResultEntities.java
index bc4dc37f..500c8ac2 100644
--- a/src/main/java/edu/ie3/simona/api/data/results/ontology/RequestResultEntities.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/result/RequestResultEntities.java
@@ -4,7 +4,10 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.results.ontology;
+package edu.ie3.simona.api.ontology.result;
+
+import java.util.List;
+import java.util.UUID;
 
 import java.util.List;
 import java.util.UUID;
diff --git a/src/main/java/edu/ie3/simona/api/data/results/ontology/ResultDataMessageFromExt.java b/src/main/java/edu/ie3/simona/api/ontology/result/ResultDataMessageFromExt.java
similarity index 74%
rename from src/main/java/edu/ie3/simona/api/data/results/ontology/ResultDataMessageFromExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/result/ResultDataMessageFromExt.java
index 83b2e318..13fa9ce3 100644
--- a/src/main/java/edu/ie3/simona/api/data/results/ontology/ResultDataMessageFromExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/result/ResultDataMessageFromExt.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.results.ontology;
+package edu.ie3.simona.api.ontology.result;
 
-import edu.ie3.simona.api.data.ontology.DataMessageFromExt;
+import edu.ie3.simona.api.ontology.DataMessageFromExt;
 
 /** Messages that are sent from an external simulation to the SIMONA */
 public interface ResultDataMessageFromExt extends DataMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/data/results/ontology/ResultDataResponseMessageToExt.java b/src/main/java/edu/ie3/simona/api/ontology/result/ResultDataResponseMessageToExt.java
similarity index 75%
rename from src/main/java/edu/ie3/simona/api/data/results/ontology/ResultDataResponseMessageToExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/result/ResultDataResponseMessageToExt.java
index 311ff1f4..a01dd96a 100644
--- a/src/main/java/edu/ie3/simona/api/data/results/ontology/ResultDataResponseMessageToExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/result/ResultDataResponseMessageToExt.java
@@ -4,9 +4,9 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.data.results.ontology;
+package edu.ie3.simona.api.ontology.result;
 
-import edu.ie3.simona.api.data.ontology.DataResponseMessageToExt;
+import edu.ie3.simona.api.ontology.DataResponseMessageToExt;
 
 /** Messages that are sent from SIMONA to the external simulation that needs results */
 public interface ResultDataResponseMessageToExt extends DataResponseMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ontology/ActivationMessage.java b/src/main/java/edu/ie3/simona/api/ontology/simulation/ActivationMessage.java
similarity index 88%
rename from src/main/java/edu/ie3/simona/api/simulation/ontology/ActivationMessage.java
rename to src/main/java/edu/ie3/simona/api/ontology/simulation/ActivationMessage.java
index f6b7f133..0b8784df 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ontology/ActivationMessage.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/simulation/ActivationMessage.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.ontology;
+package edu.ie3.simona.api.ontology.simulation;
 
 /**
  * Message that the external simulation is activated with by SIMONA
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ontology/CompletionMessage.java b/src/main/java/edu/ie3/simona/api/ontology/simulation/CompletionMessage.java
similarity index 90%
rename from src/main/java/edu/ie3/simona/api/simulation/ontology/CompletionMessage.java
rename to src/main/java/edu/ie3/simona/api/ontology/simulation/CompletionMessage.java
index 35364c9b..ae8eb12e 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ontology/CompletionMessage.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/simulation/CompletionMessage.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.ontology;
+package edu.ie3.simona.api.ontology.simulation;
 
 import java.util.Optional;
 
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ontology/ControlMessageToExt.java b/src/main/java/edu/ie3/simona/api/ontology/simulation/ControlMessageToExt.java
similarity index 86%
rename from src/main/java/edu/ie3/simona/api/simulation/ontology/ControlMessageToExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/simulation/ControlMessageToExt.java
index 601b1624..b0de22f2 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ontology/ControlMessageToExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/simulation/ControlMessageToExt.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.ontology;
+package edu.ie3.simona.api.ontology.simulation;
 
 /** Interface for control messages from the SIMONA to the external simulation */
 public interface ControlMessageToExt {}
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ontology/ControlResponseMessageFromExt.java b/src/main/java/edu/ie3/simona/api/ontology/simulation/ControlResponseMessageFromExt.java
similarity index 86%
rename from src/main/java/edu/ie3/simona/api/simulation/ontology/ControlResponseMessageFromExt.java
rename to src/main/java/edu/ie3/simona/api/ontology/simulation/ControlResponseMessageFromExt.java
index f3df0973..418f69da 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ontology/ControlResponseMessageFromExt.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/simulation/ControlResponseMessageFromExt.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.ontology;
+package edu.ie3.simona.api.ontology.simulation;
 
 /** Interface for control messages from the external simulation to SIMONA */
 public interface ControlResponseMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ontology/TerminationCompleted.java b/src/main/java/edu/ie3/simona/api/ontology/simulation/TerminationCompleted.java
similarity index 87%
rename from src/main/java/edu/ie3/simona/api/simulation/ontology/TerminationCompleted.java
rename to src/main/java/edu/ie3/simona/api/ontology/simulation/TerminationCompleted.java
index c46ca045..35d4c90c 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ontology/TerminationCompleted.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/simulation/TerminationCompleted.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.ontology;
+package edu.ie3.simona.api.ontology.simulation;
 
 /** Message returned to SIMONA indicating that the external simulation terminated */
 public record TerminationCompleted() implements ControlResponseMessageFromExt {}
diff --git a/src/main/java/edu/ie3/simona/api/simulation/ontology/TerminationMessage.java b/src/main/java/edu/ie3/simona/api/ontology/simulation/TerminationMessage.java
similarity index 90%
rename from src/main/java/edu/ie3/simona/api/simulation/ontology/TerminationMessage.java
rename to src/main/java/edu/ie3/simona/api/ontology/simulation/TerminationMessage.java
index c281d041..d406129c 100644
--- a/src/main/java/edu/ie3/simona/api/simulation/ontology/TerminationMessage.java
+++ b/src/main/java/edu/ie3/simona/api/ontology/simulation/TerminationMessage.java
@@ -4,7 +4,7 @@
  * Research group Distribution grid planning and operation
  */
 
-package edu.ie3.simona.api.simulation.ontology;
+package edu.ie3.simona.api.ontology.simulation;
 
 /**
  * Message that is sent once SIMONA is terminating, indicating that the external simulation should
diff --git a/src/test/groovy/edu/ie3/simona/api/data/connection/ExtEvDataConnectionTest.groovy b/src/test/groovy/edu/ie3/simona/api/data/connection/ExtEvDataConnectionTest.groovy
index 581efacc..905bd407 100644
--- a/src/test/groovy/edu/ie3/simona/api/data/connection/ExtEvDataConnectionTest.groovy
+++ b/src/test/groovy/edu/ie3/simona/api/data/connection/ExtEvDataConnectionTest.groovy
@@ -1,9 +1,16 @@
 package edu.ie3.simona.api.data.connection
 
-import edu.ie3.simona.api.data.ev.model.EvModel
-import edu.ie3.simona.api.data.ev.ontology.*
-import edu.ie3.simona.api.data.ontology.DataMessageFromExt
-import edu.ie3.simona.api.data.ontology.ScheduleDataServiceMessage
+
+import edu.ie3.simona.api.data.model.ev.EvModel
+import edu.ie3.simona.api.ontology.DataMessageFromExt
+import edu.ie3.simona.api.ontology.ScheduleDataServiceMessage
+import edu.ie3.simona.api.ontology.ev.ProvideArrivingEvs
+import edu.ie3.simona.api.ontology.ev.ProvideCurrentPrices
+import edu.ie3.simona.api.ontology.ev.ProvideDepartingEvs
+import edu.ie3.simona.api.ontology.ev.ProvideEvcsFreeLots
+import edu.ie3.simona.api.ontology.ev.RequestCurrentPrices
+import edu.ie3.simona.api.ontology.ev.RequestDepartingEvs
+import edu.ie3.simona.api.ontology.ev.RequestEvcsFreeLots
 import org.apache.pekko.actor.testkit.typed.javadsl.ActorTestKit
 import spock.lang.Shared
 import spock.lang.Specification
diff --git a/src/test/groovy/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingSourceTest.groovy b/src/test/groovy/edu/ie3/simona/api/mapping/ExtEntityMappingSourceTest.groovy
similarity index 96%
rename from src/test/groovy/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingSourceTest.groovy
rename to src/test/groovy/edu/ie3/simona/api/mapping/ExtEntityMappingSourceTest.groovy
index ebebf43f..d3bd6999 100644
--- a/src/test/groovy/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingSourceTest.groovy
+++ b/src/test/groovy/edu/ie3/simona/api/mapping/ExtEntityMappingSourceTest.groovy
@@ -1,4 +1,4 @@
-package edu.ie3.simona.api.simulation.mapping
+package edu.ie3.simona.api.mapping
 
 import edu.ie3.datamodel.models.input.NodeInput
 import edu.ie3.simona.api.mapping.DataType
diff --git a/src/test/groovy/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingTest.groovy b/src/test/groovy/edu/ie3/simona/api/mapping/ExtEntityMappingTest.groovy
similarity index 100%
rename from src/test/groovy/edu/ie3/simona/api/simulation/mapping/ExtEntityMappingTest.groovy
rename to src/test/groovy/edu/ie3/simona/api/mapping/ExtEntityMappingTest.groovy
diff --git a/src/test/resources/edu/ie3/simona/api/simulation/mapping/ext_entity_mapping.csv b/src/test/resources/edu/ie3/simona/api/mapping/ext_entity_mapping.csv
similarity index 100%
rename from src/test/resources/edu/ie3/simona/api/simulation/mapping/ext_entity_mapping.csv
rename to src/test/resources/edu/ie3/simona/api/mapping/ext_entity_mapping.csv