diff --git a/changelog/unreleased/issue-14480.toml b/changelog/unreleased/issue-14480.toml
new file mode 100644
index 000000000000..d675f701450d
--- /dev/null
+++ b/changelog/unreleased/issue-14480.toml
@@ -0,0 +1,5 @@
+type = "fixed"
+message = "Keep the share settings of an event definition populated when navigating between wizard steps."
+
+issues = ["Graylog2/graylog-plugin-enterprise#14480"]
+pulls = ["26990"]
diff --git a/graylog2-web-interface/src/components/event-definitions/event-definition-form/EventDefinitionFormContainer.test.tsx b/graylog2-web-interface/src/components/event-definitions/event-definition-form/EventDefinitionFormContainer.test.tsx
index 390a1f0ee297..7161d4432772 100644
--- a/graylog2-web-interface/src/components/event-definitions/event-definition-form/EventDefinitionFormContainer.test.tsx
+++ b/graylog2-web-interface/src/components/event-definitions/event-definition-form/EventDefinitionFormContainer.test.tsx
@@ -16,10 +16,14 @@
  */
 
 import * as React from 'react';
+import * as Immutable from 'immutable';
 import { render, screen } from 'wrappedTestingLibrary';
 import userEvent from '@testing-library/user-event';
 import { defaultUser as mockDefaultUser } from 'defaultMockValues';
 
+import selectEvent from 'helpers/selectEvent';
+import EntityShareDomain from 'domainActions/permissions/EntityShareDomain';
+import { createEntityShareState, everyone, viewer } from 'fixtures/entityShareState';
 import useLocation from 'routing/useLocation';
 import useSendTelemetry from 'logic/telemetry/useSendTelemetry';
 import { asMock } from 'helpers/mocking';
@@ -198,6 +202,14 @@ jest.mock('logic/telemetry/withTelemetry', () => ({
   ),
 }));
 
+jest.mock('domainActions/permissions/EntityShareDomain', () => ({
+  __esModule: true,
+  default: { prepare: jest.fn(() => Promise.resolve()), update: jest.fn(() => Promise.resolve()) },
+}));
+
+// Rendered once the form is dirty and relies on `useBlocker`, which needs a data router.
+jest.mock('components/common/ConfirmLeaveDialog', () => () => null);
+
 jest.mock('components/event-definitions/hooks/useEventDefinitionConfigFromLocalStorage');
 jest.mock('routing/useLocation');
 jest.mock('logic/telemetry/useSendTelemetry');
@@ -358,4 +370,31 @@ describe('EventDefinitionFormContainer', () => {
 
     expect(screen.getByRole('button', { name: /update event definition/i })).toBeVisible();
   });
+
+  it('keeps the selected collaborators when navigating away from and back to the Share step', async () => {
+    // Mirrors the server: the prepared state reflects exactly the capabilities that were sent.
+    asMock(EntityShareDomain.prepare).mockImplementation((_type, _title, _grn, payload?: any) =>
+      Promise.resolve(
+        createEntityShareState
+          .toBuilder()
+          .selectedGranteeCapabilities(payload?.selected_grantee_capabilities ?? Immutable.Map())
+          .build(),
+      ),
+    );
+
+    render(<EventDefinitionFormContainer action="create" eventDefinition={mockAggregationEventDefinition} />);
+
+    await userEvent.click(await screen.findByRole('button', { name: /^share$/i }));
+
+    await selectEvent.chooseOption('Search for users and teams', everyone.title);
+    await selectEvent.chooseOption('Select a capability', viewer.title);
+    await userEvent.click(await screen.findByRole('button', { name: /add collaborator/i }));
+
+    expect(await screen.findByText(everyone.title)).toBeVisible();
+
+    await userEvent.click(await screen.findByRole('button', { name: /^summary$/i }));
+    await userEvent.click(await screen.findByRole('button', { name: /^share$/i }));
+
+    expect(await screen.findByText(everyone.title)).toBeVisible();
+  });
 });
diff --git a/graylog2-web-interface/src/components/event-definitions/event-definition-form/ShareForm.tsx b/graylog2-web-interface/src/components/event-definitions/event-definition-form/ShareForm.tsx
index ba9d5a4bfb64..af008ecadba9 100644
--- a/graylog2-web-interface/src/components/event-definitions/event-definition-form/ShareForm.tsx
+++ b/graylog2-web-interface/src/components/event-definitions/event-definition-form/ShareForm.tsx
@@ -26,7 +26,7 @@ import type { EventDefinition } from '../event-definitions-types';
 
 type Props = {
   onChange: (name: string, value: EntitySharePayload) => void;
-  eventDefinition: EventDefinition;
+  eventDefinition: EventDefinition & { share_request?: EntitySharePayload };
 };
 
 const ShareForm = ({ onChange, eventDefinition }: Props) => {
@@ -49,6 +49,7 @@ const ShareForm = ({ onChange, eventDefinition }: Props) => {
           entityType="event_definition"
           entityTitle=""
           dependenciesGRN={[...streamDependenciesGRN, ...notificationDependenciesGRN]}
+          defaultSharePayload={eventDefinition?.share_request}
         />
       </Col>
     </Row>
diff --git a/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.test.tsx b/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.test.tsx
index f0341ea2bb1b..6f3a9950e1f2 100644
--- a/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.test.tsx
+++ b/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.test.tsx
@@ -15,6 +15,7 @@
  * <http://www.mongodb.com/licensing/server-side-public-license>.
  */
 import * as React from 'react';
+import * as mockImmutable from 'immutable';
 import { render, waitFor, screen } from 'wrappedTestingLibrary';
 import userEvent from '@testing-library/user-event';
 
@@ -34,7 +35,7 @@ jest.mock('domainActions/permissions/EntityShareDomain', () => ({
     update: jest.fn(() => Promise.resolve()),
     loadUserSharesPaginated: jest.fn(() =>
       Promise.resolve({
-        list: require('immutable').List(),
+        list: mockImmutable.List(),
         pagination: { page: 1, perPage: 10, query: '', total: 0, count: 0 },
       }),
     ),
@@ -90,7 +91,40 @@ describe('EntityCreateShareFormGroup', () => {
     render(<SUT />);
 
     await waitFor(() => {
-      expect(EntityShareDomain.prepare).toHaveBeenCalledWith(mockEntity.entityType, '', mockEntity.entityId, {});
+      expect(EntityShareDomain.prepare).toHaveBeenCalledWith(mockEntity.entityType, '', mockEntity.entityId, {
+        prepare_request: null,
+      });
+    });
+  });
+
+  it('restores a previously made selection from the default share payload', async () => {
+    const selected_grantee_capabilities = createEntityShareState.selectedGranteeCapabilities.merge({
+      [everyone.id]: viewer.id,
+    });
+
+    render(<SUT defaultSharePayload={{ selected_grantee_capabilities }} />);
+
+    await waitFor(() => {
+      expect(EntityShareDomain.prepare).toHaveBeenCalledWith(mockEntity.entityType, '', mockEntity.entityId, {
+        selected_grantee_capabilities,
+        prepare_request: null,
+      });
+    });
+  });
+
+  it('re-runs the dependency check when restoring a selection', async () => {
+    const selected_grantee_capabilities = createEntityShareState.selectedGranteeCapabilities.merge({
+      [everyone.id]: viewer.id,
+    });
+    const dependenciesGRN = ['grn::::stream:stream-id'];
+
+    render(<SUT defaultSharePayload={{ selected_grantee_capabilities }} dependenciesGRN={dependenciesGRN} />);
+
+    await waitFor(() => {
+      expect(EntityShareDomain.prepare).toHaveBeenCalledWith(mockEntity.entityType, '', mockEntity.entityId, {
+        selected_grantee_capabilities,
+        prepare_request: dependenciesGRN,
+      });
     });
   });
 
diff --git a/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.tsx b/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.tsx
index 80f3eaf69916..762b668658e4 100644
--- a/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.tsx
+++ b/graylog2-web-interface/src/components/permissions/EntityCreateShareFormGroup.tsx
@@ -86,13 +86,21 @@ const EntityCreateShareFormGroup = ({
   );
   const PluggableEntityShareFormGroup = usePluggableEntityShareFormGroup();
 
+  // Serialized because callers build `dependenciesGRN` inline, so its identity changes every render.
+  const dependenciesKey = JSON.stringify(dependenciesGRN ?? []);
+
   useEffect(() => {
     const { selected_collections: _, ...rest } = defaultSharePayload ?? {};
+    const dependencies: Array<GRN> = JSON.parse(dependenciesKey);
+    // Restoring a selection has to re-run the dependency check, or the missing dependency
+    // warnings shown before would silently disappear.
+    const prepare_request =
+      (rest.selected_grantee_capabilities?.size ?? 0) > 0 && dependencies.length > 0 ? dependencies : null;
 
-    EntityShareDomain.prepare(entityType, entityTitle, entityGRN, rest).then((state) => {
+    EntityShareDomain.prepare(entityType, entityTitle, entityGRN, { ...rest, prepare_request }).then((state) => {
       setEntityShareState(entityGRN, state);
     });
-  }, [entityType, entityTitle, entityGRN, defaultSharePayload, setEntityShareState]);
+  }, [entityType, entityTitle, entityGRN, defaultSharePayload, dependenciesKey, setEntityShareState]);
 
   const resetSelection = () => {
     setDisableSubmit(false);
@@ -202,6 +210,8 @@ const EntityCreateShareFormGroup = ({
             availableGrantees={entityShareState.availableGrantees}
           />
           {PluggableEntityShareFormGroup && (
+            /* Resolved from the plugin store at render time and cannot be hoisted. */
+            /* eslint-disable-next-line react-hooks/static-components */
             <PluggableEntityShareFormGroup
               entityType={entityType}
               onChange={handleAdditionalFormChange}