diff --git a/OMDSServiceDefinition/doc/ON_3 Vertragsbestand/ON_3.04 Vertragsänderungen.docx b/OMDSServiceDefinition/doc/ON_3 Vertragsbestand/ON_3.04 Vertragsänderungen.docx
index 76506d3f..18264df4 100644
Binary files a/OMDSServiceDefinition/doc/ON_3 Vertragsbestand/ON_3.04 Vertragsänderungen.docx and b/OMDSServiceDefinition/doc/ON_3 Vertragsbestand/ON_3.04 Vertragsänderungen.docx differ
diff --git a/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3Services.wsdl b/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3Services.wsdl
index 987a330b..c38db560 100644
--- a/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3Services.wsdl
+++ b/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3Services.wsdl
@@ -18,6 +18,7 @@ xmlns:boaU="urn:at.vvo.omds.types.omds3types.v1-4-0.on2antrag.unfall"
 xmlns:boaL="urn:at.vvo.omds.types.omds3types.v1-5-0.on2antrag.leben"
 xmlns:boaKr="urn:at.vvo.omds.types.omds3types.v1-6-0.on2antrag.kranken"
 xmlns:sch="urn:at.vvo.omds.types.omds3types.v1-4-0.on7schaden"
+xmlns:v="urn:at.vvo.omds.types.omds3types.v2025-27.on3vertrag"
 xmlns="http://schemas.xmlsoap.org/wsdl/"
 xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/"
 xmlns:ns="http://www.w3.org/2001/XMLSchema"
@@ -36,6 +37,7 @@ xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 			<import namespace="urn:at.vvo.omds.types.omds3types.v1-4-0.on2antrag.unfall" schemaLocation="omds3_ON2_Antrag_Unfall.xsd"/>
 			<import namespace="urn:at.vvo.omds.types.omds3types.v1-6-0.on2antrag.kranken" schemaLocation="omds3_ON2_Antrag_Kranken.xsd"/>
 			<import namespace="urn:at.vvo.omds.types.omds3types.v1-5-0.on2antrag.leben" schemaLocation="omds3_ON2_Antrag_Leben.xsd"/>
+			<import namespace="urn:at.vvo.omds.types.omds3types.v2025-27.on3vertrag" schemaLocation="omds3_ON3_Vertrag.xsd"/>
 			<import namespace="urn:at.vvo.omds.types.omds3types.v1-4-0.on7schaden" schemaLocation="omds3_ON7_Schaden.xsd"/>
 		</schema>
 	</types>
@@ -413,6 +415,33 @@ xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 		<part name="param" element="boa:ProductProposalResponse"/>
 	</message>
 
+	<!-- Vertragsänderung, Konvertierung -->
+	<message name="ContractChangeOptionsRequestMsg">
+		<part name="param" element="v:ContractChangeOptionsRequest"/>
+	</message>
+	<message name="ContractChangeOptionsResponseMsg">
+		<part name="param" element="v:ContractChangeOptionsResponse"/>
+	</message>
+	<message name="ContractChangeProposalRequestMsg">
+		<part name="param" element="v:ContractChangeProposalRequest"/>
+	</message>
+	<message name="ContractChangeProposalResponseMsg">
+		<part name="param" element="v:ContractChangeProposalResponse"/>
+	</message>
+	<message name="ContractChangeConfigurationRequestMsg">
+		<part name="param" element="v:ContractChangeConfigurationRequest"/>
+	</message>
+	<message name="ContractChangeConfigurationResponseMsg">
+		<part name="param" element="v:ContractChangeConfigurationResponse"/>
+	</message>
+	<message name="ContractChangeSubmitRequestMsg">
+		<part name="param" element="v:ContractChangeSubmitRequest"/>
+	</message>
+	<message name="ContractChangeSubmitResponseMsg">
+		<part name="param" element="v:ContractChangeSubmitResponse"/>
+	</message>
+
+
 	<!-- Fehler -->
 	<message name="ServiceFaultMsg">
 		<part name="param" element="cst:serviceFault" />
@@ -728,6 +757,31 @@ xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 			<fault name="ProductProposalFault" message="os:ServiceFaultMsg"/>
 		</operation>
 
+		<operation name="contractChangeOptions">
+			<input name="ContractChangeOptionsRequestPort" message="os:ContractChangeOptionsRequestMsg"/>
+			<output name="ContractChangeOptionsResponsePort" message="os:ContractChangeOptionsResponseMsg"/>
+			<fault name="ContractChangeOptionsFault" message="os:ServiceFaultMsg"/>
+		</operation>
+		<operation name="contractChangeProposal">
+			<input name="ContractChangeProposalRequestPort" message="os:ContractChangeProposalRequestMsg"/>
+			<output name="ContractChangeProposalResponsePort" message="os:ContractChangeProposalResponseMsg"/>
+			<fault name="ContractChangeProposalFault" message="os:ServiceFaultMsg"/>
+		</operation>
+		<operation name="contractChangeProposal">
+			<input name="ContractChangeProposalRequestPort" message="os:ContractChangeProposalRequestMsg"/>
+			<output name="ContractChangeProposalResponsePort" message="os:ContractChangeProposalResponseMsg"/>
+			<fault name="ContractChangeProposalFault" message="os:ServiceFaultMsg"/>
+		</operation>
+		<operation name="contractChangeConfiguration">
+			<input name="ContractChangeConfigurationRequestPort" message="os:ContractChangeConfigurationRequestMsg"/>
+			<output name="ContractChangeConfigurationResponsePort" message="os:ContractChangeConfigurationResponseMsg"/>
+			<fault name="ContractChangeConfigurationFault" message="os:ServiceFaultMsg"/>
+		</operation>
+		<operation name="contractChangeSubmit">
+			<input name="ContractChangeSubmitRequestPort" message="os:ContractChangeSubmitRequestMsg"/>
+			<output name="ContractChangeSubmitResponsePort" message="os:ContractChangeSubmitResponseMsg"/>
+			<fault name="ContractChangeSubmitFault" message="os:ServiceFaultMsg"/>
+		</operation>
 	</portType>
 
 	<binding name="omdsServicePortBinding" type="os:omdsServicePortType">
@@ -1475,6 +1529,31 @@ xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 				<soap:fault name="ProductProposalFault" use="literal"/>
 			</fault>
 		</operation>
+
+		<operation name="contractChangeOptions">
+			<soap:operation soapAction="urn:contractChangeOptions" style="document"/>
+			<input name="ContractChangeOptionsRequestPort"><soap:body use="literal"/></input>
+			<output name="ContractChangeOptionsResponsePort"><soap:body use="literal"/></output>
+			<fault name="ContractChangeOptionsFault"><soap:fault name="ContractChangeOptionsFault" use="literal"/></fault>
+		</operation>
+		<operation name="contractChangeProposal">
+			<soap:operation soapAction="urn:contractChangeProposal" style="document"/>
+			<input name="ContractChangeProposalRequestPort"><soap:body use="literal"/></input>
+			<output name="ContractChangeProposalResponsePort"><soap:body use="literal"/></output>
+			<fault name="ContractChangeProposalFault"><soap:fault name="ContractChangeProposalFault" use="literal"/></fault>
+		</operation>
+		<operation name="contractChangeConfiguration">
+			<soap:operation soapAction="urn:contractChangeConfiguration" style="document"/>
+			<input name="ContractChangeConfigurationRequestPort"><soap:body use="literal"/></input>
+			<output name="ContractChangeConfigurationResponsePort"><soap:body use="literal"/></output>
+			<fault name="ContractChangeConfigurationFault"><soap:fault name="ContractChangeConfigurationFault" use="literal"/></fault>
+		</operation>
+		<operation name="contractChangeSubmit">
+			<soap:operation soapAction="urn:contractChangeSubmit" style="document"/>
+			<input name="ContractChangeSubmitRequestPort"><soap:body use="literal"/></input>
+			<output name="ContractChangeSubmitResponsePort"><soap:body use="literal"/></output>
+			<fault name="ContractChangeSubmitFault"><soap:fault name="ContractChangeSubmitFault" use="literal"/></fault>
+		</operation>
 	</binding>
 
 	<service name="omdsService">
diff --git a/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3_ON3_Vertrag.xsd b/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3_ON3_Vertrag.xsd
new file mode 100644
index 00000000..dcc9e6d9
--- /dev/null
+++ b/OMDSServiceDefinition/src/main/resources/def/r2025_27/omds3_ON3_Vertrag.xsd
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<xsd:schema xmlns="urn:at.vvo.omds.types.omds3types.v2025-27.on3vertrag"
+            xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:omds="urn:omds20"
+            xmlns:cst="urn:omds3CommonServiceTypes-1-1-0"
+            targetNamespace="urn:at.vvo.omds.types.omds3types.v2025-27.on3vertrag"
+            elementFormDefault="qualified" attributeFormDefault="qualified" version="2025.27-MINOR">
+  <xsd:import namespace="urn:omds20" schemaLocation="omds217-00.xsd"/>
+  <xsd:import namespace="urn:omds3CommonServiceTypes-1-1-0" schemaLocation="omds3CommonServiceTypes.xsd"/> 
+  <xsd:element name="ContractChangeOptionsRequest" />
+  <xsd:element name="ContractChangeOptionsResponse" />
+  <xsd:element name="ContractChangeProposalRequest" />
+  <xsd:element name="ContractChangeProposalResponse" />
+  <xsd:element name="ContractChangeConfigurationRequest" />
+  <xsd:element name="ContractChangeConfigurationResponse" />
+  <xsd:element name="ContractChangeSubmitRequest" />
+  <xsd:element name="ContractChangeSubmitResponse" />
+</xsd:schema>
\ No newline at end of file