diff --git a/graph/graph-core-services/src/main/kotlin/org/orkg/graph/domain/ResourceService.kt b/graph/graph-core-services/src/main/kotlin/org/orkg/graph/domain/ResourceService.kt
index 12c876c00..1b665b10e 100644
--- a/graph/graph-core-services/src/main/kotlin/org/orkg/graph/domain/ResourceService.kt
+++ b/graph/graph-core-services/src/main/kotlin/org/orkg/graph/domain/ResourceService.kt
@@ -124,42 +124,41 @@ class ResourceService(
             .orElseThrow { ResourceNotFound.withId(id) }
 
     override fun update(command: UpdateCommand) {
-        if (!command.hasNoContents()) {
-            val resource = repository.findById(command.id)
-                .orElseThrow { ResourceNotFound.withId(command.id) }
-            if (!resource.modifiable) {
-                throw ResourceNotModifiable(command.id)
-            }
-            command.label?.also { Label.ofOrNull(it) ?: throw InvalidLabel() }
-            command.classes?.also { validateClasses(it) }
-            command.observatoryId?.let { observatoryId ->
-                if (observatoryId != resource.observatoryId && !observatoryRepository.existsById(observatoryId)) {
-                    throw ObservatoryNotFound(observatoryId)
-                }
-            }
-            command.organizationId?.let { organizationId ->
-                if (organizationId != resource.organizationId && organizationRepository.findById(organizationId).isEmpty) {
-                    throw OrganizationNotFound(organizationId)
-                }
+        if (command.hasNoContents()) return
+        val resource = repository.findById(command.id)
+            .orElseThrow { ResourceNotFound.withId(command.id) }
+        if (!resource.modifiable) {
+            throw ResourceNotModifiable(command.id)
+        }
+        command.label?.also { Label.ofOrNull(it) ?: throw InvalidLabel() }
+        command.classes?.also { validateClasses(it) }
+        command.observatoryId?.let { observatoryId ->
+            if (observatoryId != resource.observatoryId && observatoryId != ObservatoryId.UNKNOWN && !observatoryRepository.existsById(observatoryId)) {
+                throw ObservatoryNotFound(observatoryId)
             }
-            val contributor by lazy {
-                contributorRepository.findById(command.contributorId)
-                    .orElseThrow { ContributorNotFound(command.contributorId) }
+        }
+        command.organizationId?.let { organizationId ->
+            if (organizationId != resource.organizationId && organizationId != OrganizationId.UNKNOWN && organizationRepository.findById(organizationId).isEmpty) {
+                throw OrganizationNotFound(organizationId)
             }
-            if (command.visibility != null && command.visibility != resource.visibility) {
-                if (!resource.isOwnedBy(command.contributorId) || !isAllowedVisibilityChangeByOwner(command.visibility!!, resource.visibility)) {
-                    if (!contributor.isCurator) {
-                        throw NeitherOwnerNorCurator.cannotChangeVisibility(resource.id)
-                    }
+        }
+        val contributor by lazy {
+            contributorRepository.findById(command.contributorId)
+                .orElseThrow { ContributorNotFound(command.contributorId) }
+        }
+        if (command.visibility != null && command.visibility != resource.visibility) {
+            if (!resource.isOwnedBy(command.contributorId) || !isAllowedVisibilityChangeByOwner(command.visibility!!, resource.visibility)) {
+                if (!contributor.isCurator) {
+                    throw NeitherOwnerNorCurator.cannotChangeVisibility(resource.id)
                 }
             }
-            if (command.verified != null && command.verified != resource.verified && !contributor.isCurator) {
-                throw NotACurator.cannotChangeVerifiedStatus(contributor.id)
-            }
-            val updated = resource.apply(command)
-            if (updated != resource) {
-                repository.save(updated)
-            }
+        }
+        if (command.verified != null && command.verified != resource.verified && !contributor.isCurator) {
+            throw NotACurator.cannotChangeVerifiedStatus(contributor.id)
+        }
+        val updated = resource.apply(command)
+        if (updated != resource) {
+            repository.save(updated)
         }
     }
 
diff --git a/graph/graph-core-services/src/test/kotlin/org/orkg/graph/domain/ResourceServiceUnitTest.kt b/graph/graph-core-services/src/test/kotlin/org/orkg/graph/domain/ResourceServiceUnitTest.kt
index 838727a53..1f6925251 100644
--- a/graph/graph-core-services/src/test/kotlin/org/orkg/graph/domain/ResourceServiceUnitTest.kt
+++ b/graph/graph-core-services/src/test/kotlin/org/orkg/graph/domain/ResourceServiceUnitTest.kt
@@ -1,6 +1,7 @@
 package org.orkg.graph.domain
 
 import io.kotest.assertions.asClue
+import io.kotest.assertions.throwables.shouldNotThrow
 import io.kotest.assertions.throwables.shouldThrow
 import io.kotest.matchers.shouldBe
 import io.mockk.every
@@ -515,6 +516,24 @@ internal class ResourceServiceUnitTest : MockkBaseTest {
         verify(exactly = 1) { observatoryRepository.existsById(command.observatoryId!!) }
     }
 
+    @Test
+    fun `Given a resource update command, when observatory is unknown, is does not throw an exception`() {
+        val resource = createResource(observatoryId = ObservatoryId("04c4d2f9-82e0-47c3-b0ef-79c1f515a940"))
+        val command = UpdateResourceUseCase.UpdateCommand(
+            id = resource.id,
+            contributorId = ContributorId(MockUserId.USER),
+            observatoryId = ObservatoryId.UNKNOWN
+        )
+
+        every { repository.findById(resource.id) } returns Optional.of(resource)
+        every { repository.save(any()) } just runs
+
+        shouldNotThrow<ObservatoryNotFound> { service.update(command) }
+
+        verify(exactly = 1) { repository.findById(resource.id) }
+        verify(exactly = 1) { repository.save(withArg { it.observatoryId shouldBe ObservatoryId.UNKNOWN }) }
+    }
+
     @Test
     fun `Given a resource update command, when organization does not exist, it throws an exception`() {
         val resource = createResource()
@@ -533,6 +552,24 @@ internal class ResourceServiceUnitTest : MockkBaseTest {
         verify(exactly = 1) { organizationRepository.findById(command.organizationId!!) }
     }
 
+    @Test
+    fun `Given a resource update command, when organization is unknown, is does not throw an exception`() {
+        val resource = createResource(organizationId = OrganizationId("04c4d2f9-82e0-47c3-b0ef-79c1f515a940"))
+        val command = UpdateResourceUseCase.UpdateCommand(
+            id = resource.id,
+            contributorId = ContributorId(MockUserId.USER),
+            organizationId = OrganizationId.UNKNOWN
+        )
+
+        every { repository.findById(resource.id) } returns Optional.of(resource)
+        every { repository.save(any()) } just runs
+
+        shouldNotThrow<OrganizationNotFound> { service.update(command) }
+
+        verify(exactly = 1) { repository.findById(resource.id) }
+        verify(exactly = 1) { repository.save(withArg { it.organizationId shouldBe OrganizationId.UNKNOWN }) }
+    }
+
     @Test
     fun `Given a resource update command, when visibility is changed to unlisted, it sets the unlisted by metadata`() {
         val resource = createResource()