diff --git a/.gitignore b/.gitignore
index ccf4e954ec..8bafbc1f56 100644
--- a/.gitignore
+++ b/.gitignore
@@ -29,6 +29,9 @@ logs
 # Maven version backups
 */*.xml.versionsBackup
 
+# Generated by maven-shade-plugin for repackaging modules
+*/dependency-reduced-pom.xml
+
 # The following files are generated/updated by vaadin-maven-plugin
 */node_modules/
 */frontend/generated/
diff --git a/datamanager-app/pom.xml b/datamanager-app/pom.xml
index 8ed5a02dad..0385caf5f3 100644
--- a/datamanager-app/pom.xml
+++ b/datamanager-app/pom.xml
@@ -256,11 +256,6 @@
       <groupId>org.slf4j</groupId>
       <artifactId>jcl-over-slf4j</artifactId>
     </dependency>
-    <dependency>
-      <groupId>life.qbic</groupId>
-      <artifactId>openbis-api</artifactId>
-      <classifier>r1700646105</classifier>
-    </dependency>
     <dependency>
       <groupId>org.apache.tomcat.embed</groupId>
       <artifactId>tomcat-embed-core</artifactId>
diff --git a/datamanager-bom/pom.xml b/datamanager-bom/pom.xml
index 2edceacd83..9b2e186510 100644
--- a/datamanager-bom/pom.xml
+++ b/datamanager-bom/pom.xml
@@ -101,6 +101,11 @@
         <artifactId>project-management-infrastructure</artifactId>
         <version>${project.version}</version>
       </dependency>
+      <dependency>
+        <groupId>life.qbic.datamanager</groupId>
+        <artifactId>openbis-api-clean</artifactId>
+        <version>${project.version}</version>
+      </dependency>
       <dependency>
         <groupId>life.qbic.datamanager</groupId>
         <artifactId>subscription-api</artifactId>
diff --git a/domain-concept/src/main/java/life/qbic/domain/concepts/DomainEvent.java b/domain-concept/src/main/java/life/qbic/domain/concepts/DomainEvent.java
index 8239000a2f..49219285be 100644
--- a/domain-concept/src/main/java/life/qbic/domain/concepts/DomainEvent.java
+++ b/domain-concept/src/main/java/life/qbic/domain/concepts/DomainEvent.java
@@ -1,6 +1,6 @@
 package life.qbic.domain.concepts;
 
-import com.fasterxml.jackson.annotation.JsonGetter;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import java.io.Serializable;
 import java.time.Instant;
 
@@ -14,6 +14,7 @@
  */
 public abstract class DomainEvent implements Serializable {
 
+  @JsonProperty("occurredOn")
   protected final Instant occurredOn;
 
   protected DomainEvent() {
@@ -26,7 +27,6 @@ protected DomainEvent() {
    * @return the instant the of event creation.
    */
 
-  @JsonGetter("occurredOn")
   public Instant occurredOn() {
     return occurredOn;
   }
diff --git a/identity/pom.xml b/identity/pom.xml
index 29e3957072..278900d194 100644
--- a/identity/pom.xml
+++ b/identity/pom.xml
@@ -57,16 +57,10 @@
       <artifactId>application-commons</artifactId>
     </dependency>
     <dependency>
-      <groupId>com.fasterxml.jackson.core</groupId>
+      <groupId>tools.jackson.core</groupId>
       <artifactId>jackson-core</artifactId>
       <scope>test</scope>
     </dependency>
-    <dependency>
-      <groupId>com.fasterxml.jackson.datatype</groupId>
-      <artifactId>jackson-datatype-jsr310</artifactId>
-      <version>${jackson-2-bom.version}</version>
-      <scope>test</scope>
-    </dependency>
     <dependency>
       <groupId>org.jobrunr</groupId>
       <artifactId>jobrunr</artifactId>
@@ -85,6 +79,11 @@
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-annotations</artifactId>
     </dependency>
+    <dependency>
+      <groupId>tools.jackson.core</groupId>
+      <artifactId>jackson-databind</artifactId>
+      <scope>test</scope>
+    </dependency>
 
 
   </dependencies>
diff --git a/identity/src/test/groovy/life/qbic/identity/domain/user/event/UserRegisteredEventSpec.groovy b/identity/src/test/groovy/life/qbic/identity/domain/user/event/UserRegisteredEventSpec.groovy
index 8165ffefeb..bd9019ff7c 100644
--- a/identity/src/test/groovy/life/qbic/identity/domain/user/event/UserRegisteredEventSpec.groovy
+++ b/identity/src/test/groovy/life/qbic/identity/domain/user/event/UserRegisteredEventSpec.groovy
@@ -1,19 +1,17 @@
 package life.qbic.identity.domain.user.event
 
-import com.fasterxml.jackson.databind.ObjectMapper
-import com.fasterxml.jackson.databind.json.JsonMapper
-import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule
 import life.qbic.identity.domain.event.UserRegistered
 import spock.lang.Specification
+import tools.jackson.databind.ObjectMapper
 
 class UserRegisteredEventSpec extends Specification {
 
     def "Ensure serialisation and deserialisation"() {
         given:
         UserRegistered userRegistered = UserRegistered.create("1234", "Sven", "sven.fillinger@test.de")
+        ObjectMapper objectMapper = new ObjectMapper();
 
         when:
-        ObjectMapper objectMapper = JsonMapper.builder().addModule(new JavaTimeModule()).build()
         String json = objectMapper.writeValueAsString(userRegistered)
         UserRegistered deserialised = objectMapper.readValue(json, UserRegistered)
 
diff --git a/openbis-api-clean/pom.xml b/openbis-api-clean/pom.xml
new file mode 100644
index 0000000000..3723a8d178
--- /dev/null
+++ b/openbis-api-clean/pom.xml
@@ -0,0 +1,167 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>life.qbic.datamanager</groupId>
+    <artifactId>datamanager</artifactId>
+    <version>1.15.0</version>
+  </parent>
+
+  <artifactId>openbis-api-clean</artifactId>
+  <name>OpenBIS API (de-collided)</name>
+  <description>
+    Repackaging of the upstream life.qbic:openbis-api shaded uber-jar that relocates bundled
+    third-party packages into a private namespace.
+
+    Rationale: the upstream artifact is a shaded uber-jar that bundles old (2017-era) copies of
+    third-party libraries under the same fully-qualified names as the real runtime dependencies.
+    Depending on classpath ordering these collide with the real libraries. Relocating them to
+    life.qbic.openbis.shaded.* rewrites both the bundled class files and the references inside the
+    openbis client classes, so openbis keeps behaving exactly as before while the real libraries
+    remain the single source of those types at compile time and runtime.
+  </description>
+
+  <dependencies>
+    <!--
+      Input of the relocation only. It is marked optional and removed from the reduced
+      published POM, so consumers never see the upstream shaded jar again - they receive just the
+      relocated openbis classes and rely on the real libraries for third-party types.
+    -->
+    <dependency>
+      <groupId>life.qbic</groupId>
+      <artifactId>openbis-api</artifactId>
+      <version>20.10.7.3</version>
+      <classifier>r1700646105</classifier>
+      <optional>true</optional>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <!--
+        Only build the (initially empty) jar during the compile phase so maven-shade-plugin can
+        relocate the openbis dependency into it, then unpack it into target/classes. The default
+        package-phase 'default-jar' execution is disabled, otherwise it would try to re-create the
+        already-shaded main artifact at package time and fail with
+        "You have to use a classifier to attach supplemental artifacts ...".
+      -->
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.5.0</version>
+        <executions>
+          <execution>
+            <id>default-jar-early</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+          </execution>
+          <execution>
+            <id>default-jar</id>
+            <phase>none</phase>
+          </execution>
+        </executions>
+      </plugin>
+
+      <!--
+        Relocate the bundled third-party packages into a private namespace. Runs during the compile
+        phase so 'mvn compile' and other modules in the same reactor see the relocated classes in
+        target/classes (a package-only shade is invisible to same-reactor consumers).
+      -->
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-shade-plugin</artifactId>
+        <version>3.6.0</version>
+        <configuration>
+          <createDependencyReducedPom>true</createDependencyReducedPom>
+          <relocations>
+            <!--
+              Move the bundled Spring (compiled against javax.servlet, incl. the
+              org.springframework.web.WebApplicationInitializer that collides with the real Spring
+              Framework 7 / Jakarta version) into a private namespace.
+            -->
+            <relocation>
+              <pattern>org.springframework</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.org.springframework</shadedPattern>
+            </relocation>
+            <!-- Move the bundled Apache commons/http/etc. into a private namespace so it cannot
+                 shadow the real Apache commons libraries on the classpath. -->
+            <relocation>
+              <pattern>org.apache</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.org.apache</shadedPattern>
+            </relocation>
+            <!-- Move the bundled old AspectJ into a private namespace so it cannot collide with the
+                 real aspectjweaver pulled in via Spring AOP. -->
+            <relocation>
+              <pattern>org.aspectj</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.org.aspectj</shadedPattern>
+            </relocation>
+            <!-- Move the bundled Eclipse classes (e.g. EclipseLink/ASM helpers) into a private
+                 namespace so they cannot collide with Eclipse/JAXB classes on the classpath. -->
+            <relocation>
+              <pattern>org.eclipse</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.org.eclipse</shadedPattern>
+            </relocation>
+            <!-- Move the bundled old slf4j into a private namespace so it cannot shadow the real
+                 slf4j-api that the application logging facade is built against. -->
+            <relocation>
+              <pattern>org.slf4j</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.org.slf4j</shadedPattern>
+            </relocation>
+            <!-- Move the bundled AOP Alliance into a private namespace so it cannot collide with the
+                 org.aopalliance provided by Spring AOP. -->
+            <relocation>
+              <pattern>org.aopalliance</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.org.aopalliance</shadedPattern>
+            </relocation>
+            <!-- Move the bundled old Jackson into a private namespace so it cannot shadow the real
+                 com.fasterxml.jackson pulled in via Spring Boot / ro-crate. -->
+            <relocation>
+              <pattern>com.fasterxml</pattern>
+              <shadedPattern>life.qbic.openbis.shaded.com.fasterxml</shadedPattern>
+            </relocation>
+          </relocations>
+          <transformers>
+            <transformer
+              implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
+          </transformers>
+        </configuration>
+        <executions>
+          <execution>
+            <id>relocate</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>shade</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+
+      <!-- Unpack the relocated jar into target/classes so same-reactor modules find the classes. -->
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-antrun-plugin</artifactId>
+        <version>3.1.0</version>
+        <executions>
+          <execution>
+            <id>unpack-relocated</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>run</goal>
+            </goals>
+            <configuration>
+              <target>
+                <unzip src="${project.build.directory}/${project.build.finalName}.jar"
+                  dest="${project.build.outputDirectory}"/>
+              </target>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+
+</project>
\ No newline at end of file
diff --git a/pom.xml b/pom.xml
index 026216559c..c77d677e12 100644
--- a/pom.xml
+++ b/pom.xml
@@ -29,6 +29,7 @@
     <module>domain-concept</module>
     <module>identity-api</module>
     <module>identity-infrastructure</module>
+    <module>openbis-api-clean</module>
     <module>project-management-infrastructure</module>
     <module>email-service-provider</module>
     <module>finances-infrastructure</module>
diff --git a/project-management-infrastructure/pom.xml b/project-management-infrastructure/pom.xml
index ab4302eedf..94f1e791af 100644
--- a/project-management-infrastructure/pom.xml
+++ b/project-management-infrastructure/pom.xml
@@ -20,9 +20,8 @@
       <artifactId>logging</artifactId>
     </dependency>
     <dependency>
-      <groupId>life.qbic</groupId>
-      <artifactId>openbis-api</artifactId>
-      <classifier>r1700646105</classifier>
+      <groupId>life.qbic.datamanager</groupId>
+      <artifactId>openbis-api-clean</artifactId>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
@@ -98,6 +97,17 @@
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-jackson</artifactId>
     </dependency>
+    <!--
+      ro-crate-java brings jackson-databind with runtime scope only; the module's own code calls
+      into ro-crate-java APIs that expose com.fasterxml.jackson.databind.JsonNode, so jackson-databind
+      must be available on the compile classpath. (Previously this was satisfied by the bundled
+      jackson inside the shaded upstream openbis-api jar; after de-colliding openbis that jackson is
+      no longer on the classpath.)
+    -->
+    <dependency>
+      <groupId>com.fasterxml.jackson.core</groupId>
+      <artifactId>jackson-databind</artifactId>
+    </dependency>
     <!--    needed for ror creation-->
     <dependency>
       <groupId>jakarta.xml.bind</groupId>