diff --git a/apps/server/src/core/page/page-permission/dto/page-permission.dto.ts b/apps/server/src/core/page/page-permission/dto/page-permission.dto.ts
new file mode 100644
index 00000000..5a6fd4c5
--- /dev/null
+++ b/apps/server/src/core/page/page-permission/dto/page-permission.dto.ts
@@ -0,0 +1,67 @@
+import {
+  ArrayNotEmpty,
+  IsArray,
+  IsIn,
+  IsOptional,
+  IsString,
+  IsUUID,
+  ValidateIf,
+} from 'class-validator';
+
+export const PAGE_PERMISSION_ROLES = ['reader', 'writer'] as const;
+export type PagePermissionRoleValue = (typeof PAGE_PERMISSION_ROLES)[number];
+
+export class PageIdBodyDto {
+  @IsString()
+  pageId: string;
+}
+
+export class AddPagePermissionDto {
+  @IsString()
+  pageId: string;
+
+  @IsIn(PAGE_PERMISSION_ROLES as unknown as string[])
+  role: PagePermissionRoleValue;
+
+  @ValidateIf((o) => !o.groupIds || o.groupIds.length === 0)
+  @IsArray()
+  @ArrayNotEmpty()
+  @IsUUID('all', { each: true })
+  userIds?: string[];
+
+  @IsOptional()
+  @IsArray()
+  @IsUUID('all', { each: true })
+  groupIds?: string[];
+}
+
+export class RemovePagePermissionDto {
+  @IsString()
+  pageId: string;
+
+  @IsOptional()
+  @IsArray()
+  @IsUUID('all', { each: true })
+  userIds?: string[];
+
+  @IsOptional()
+  @IsArray()
+  @IsUUID('all', { each: true })
+  groupIds?: string[];
+}
+
+export class UpdatePagePermissionDto {
+  @IsString()
+  pageId: string;
+
+  @IsIn(PAGE_PERMISSION_ROLES as unknown as string[])
+  role: PagePermissionRoleValue;
+
+  @ValidateIf((o) => !o.groupId)
+  @IsUUID()
+  userId?: string;
+
+  @IsOptional()
+  @IsUUID()
+  groupId?: string;
+}
diff --git a/apps/server/src/core/page/page-permission/page-permission.controller.ts b/apps/server/src/core/page/page-permission/page-permission.controller.ts
new file mode 100644
index 00000000..86862096
--- /dev/null
+++ b/apps/server/src/core/page/page-permission/page-permission.controller.ts
@@ -0,0 +1,97 @@
+import {
+  Body,
+  Controller,
+  HttpCode,
+  HttpStatus,
+  Post,
+  UseGuards,
+} from '@nestjs/common';
+import { JwtAuthGuard } from '../../../common/guards/jwt-auth.guard';
+import { AuthUser } from '../../../common/decorators/auth-user.decorator';
+import { User } from '@docmost/db/types/entity.types';
+import { PaginationOptions } from '@docmost/db/pagination/pagination-options';
+import { PagePermissionService } from './page-permission.service';
+import {
+  AddPagePermissionDto,
+  PageIdBodyDto,
+  RemovePagePermissionDto,
+  UpdatePagePermissionDto,
+} from './dto/page-permission.dto';
+
+/**
+ * Page-sharing endpoints — Outline-style granular access.
+ * Mounted under the same /pages prefix as PageController, so the existing
+ * client (`apps/client/src/ee/page-permission/services/page-permission-service.ts`)
+ * works without any URL changes.
+ */
+@UseGuards(JwtAuthGuard)
+@Controller('pages')
+export class PagePermissionController {
+  constructor(private readonly pagePermissionService: PagePermissionService) {}
+
+  @HttpCode(HttpStatus.NO_CONTENT)
+  @Post('restrict')
+  async restrict(@Body() dto: PageIdBodyDto, @AuthUser() user: User) {
+    await this.pagePermissionService.restrictPage(dto.pageId, user);
+  }
+
+  @HttpCode(HttpStatus.NO_CONTENT)
+  @Post('remove-restriction')
+  async unrestrict(@Body() dto: PageIdBodyDto, @AuthUser() user: User) {
+    await this.pagePermissionService.unrestrictPage(dto.pageId, user);
+  }
+
+  @HttpCode(HttpStatus.NO_CONTENT)
+  @Post('add-permission')
+  async addPermission(
+    @Body() dto: AddPagePermissionDto,
+    @AuthUser() user: User,
+  ) {
+    await this.pagePermissionService.addPermissions(dto, user);
+  }
+
+  @HttpCode(HttpStatus.NO_CONTENT)
+  @Post('remove-permission')
+  async removePermission(
+    @Body() dto: RemovePagePermissionDto,
+    @AuthUser() user: User,
+  ) {
+    await this.pagePermissionService.removePermissions(dto, user);
+  }
+
+  @HttpCode(HttpStatus.NO_CONTENT)
+  @Post('update-permission')
+  async updatePermission(
+    @Body() dto: UpdatePagePermissionDto,
+    @AuthUser() user: User,
+  ) {
+    await this.pagePermissionService.updatePermissionRole(dto, user);
+  }
+
+  @HttpCode(HttpStatus.OK)
+  @Post('permissions')
+  async listPermissions(
+    @Body() body: PageIdBodyDto & { cursor?: string; query?: string },
+    @AuthUser() user: User,
+  ) {
+    const pagination: PaginationOptions = {
+      limit: 50,
+      cursor: body.cursor,
+      query: body.query,
+    } as PaginationOptions;
+    return this.pagePermissionService.listPermissions(
+      body.pageId,
+      user,
+      pagination as any,
+    );
+  }
+
+  @HttpCode(HttpStatus.OK)
+  @Post('permission-info')
+  async getRestrictionInfo(
+    @Body() dto: PageIdBodyDto,
+    @AuthUser() user: User,
+  ) {
+    return this.pagePermissionService.getRestrictionInfo(dto.pageId, user);
+  }
+}
diff --git a/apps/server/src/core/page/page-permission/page-permission.module.ts b/apps/server/src/core/page/page-permission/page-permission.module.ts
new file mode 100644
index 00000000..b7746cc2
--- /dev/null
+++ b/apps/server/src/core/page/page-permission/page-permission.module.ts
@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { PagePermissionController } from './page-permission.controller';
+import { PagePermissionService } from './page-permission.service';
+
+@Module({
+  controllers: [PagePermissionController],
+  providers: [PagePermissionService],
+})
+export class PagePermissionModule {}
diff --git a/apps/server/src/core/page/page-permission/page-permission.service.ts b/apps/server/src/core/page/page-permission/page-permission.service.ts
new file mode 100644
index 00000000..5f001af4
--- /dev/null
+++ b/apps/server/src/core/page/page-permission/page-permission.service.ts
@@ -0,0 +1,316 @@
+import {
+  ForbiddenException,
+  Injectable,
+  NotFoundException,
+} from '@nestjs/common';
+import { InjectKysely } from 'nestjs-kysely';
+import { KyselyDB } from '@docmost/db/types/kysely.types';
+import { PagePermissionRepo } from '@docmost/db/repos/page/page-permission.repo';
+import { PageRepo } from '@docmost/db/repos/page/page.repo';
+import { Page, User } from '@docmost/db/types/entity.types';
+import { PageAccessService } from '../page-access/page-access.service';
+import {
+  PageAccessLevel,
+  PagePermissionRole,
+} from '../../../common/helpers/types/permission';
+import {
+  AddPagePermissionDto,
+  RemovePagePermissionDto,
+  UpdatePagePermissionDto,
+} from './dto/page-permission.dto';
+
+interface RestrictionInfo {
+  restrictionId?: string;
+  hasDirectRestriction: boolean;
+  hasInheritedRestriction: boolean;
+  inheritedFrom?: { id: string; slugId: string; title: string };
+  userAccess: { canView: boolean; canEdit: boolean; canManage: boolean };
+}
+
+/**
+ * Page-sharing service — Outline-style granular access on top of the native
+ * page_access / page_permissions tables. Reuses `PagePermissionRepo` for
+ * persistence and `PageAccessService` to authorize the caller.
+ *
+ * Authorization rule for managing permissions: caller must have edit access
+ * to the page (page-level if restricted, space-level otherwise). This matches
+ * Outline's "Editors can share" behavior.
+ */
+@Injectable()
+export class PagePermissionService {
+  constructor(
+    @InjectKysely() private readonly db: KyselyDB,
+    private readonly pageRepo: PageRepo,
+    private readonly pagePermissionRepo: PagePermissionRepo,
+    private readonly pageAccessService: PageAccessService,
+  ) {}
+
+  private async loadPageOrThrow(pageId: string): Promise<Page> {
+    const page = await this.pageRepo.findById(pageId);
+    if (!page) throw new NotFoundException('Page not found');
+    return page;
+  }
+
+  /**
+   * Restrict the page — promote its access level to RESTRICTED and seed the
+   * caller as a writer so they don't lock themselves out. Idempotent.
+   */
+  async restrictPage(pageId: string, user: User): Promise<void> {
+    const page = await this.loadPageOrThrow(pageId);
+    await this.pageAccessService.validateCanEdit(page, user);
+
+    await this.db.transaction().execute(async (trx) => {
+      const existing = await this.pagePermissionRepo.findPageAccessByPageId(
+        page.id,
+        trx,
+      );
+
+      let pageAccess = existing;
+      if (!pageAccess) {
+        pageAccess = await this.pagePermissionRepo.insertPageAccess(
+          {
+            pageId: page.id,
+            workspaceId: page.workspaceId,
+            spaceId: page.spaceId,
+            accessLevel: PageAccessLevel.RESTRICTED,
+            creatorId: user.id,
+          },
+          trx,
+        );
+      }
+
+      // Seed the caller as a writer so they retain access after restriction.
+      const existingPerm = await this.pagePermissionRepo.findPagePermissionByUserId(
+        pageAccess.id,
+        user.id,
+        trx,
+      );
+      if (!existingPerm) {
+        await this.pagePermissionRepo.insertPagePermissions(
+          [
+            {
+              pageAccessId: pageAccess.id,
+              userId: user.id,
+              role: PagePermissionRole.WRITER,
+              addedById: user.id,
+            },
+          ],
+          trx,
+        );
+      }
+    });
+  }
+
+  async unrestrictPage(pageId: string, user: User): Promise<void> {
+    const page = await this.loadPageOrThrow(pageId);
+    await this.pageAccessService.validateCanEdit(page, user);
+    // ON DELETE CASCADE on page_permissions handles cleanup.
+    await this.pagePermissionRepo.deletePageAccess(page.id);
+  }
+
+  async addPermissions(dto: AddPagePermissionDto, user: User): Promise<void> {
+    const page = await this.loadPageOrThrow(dto.pageId);
+    await this.pageAccessService.validateCanEdit(page, user);
+
+    const userIds = dto.userIds ?? [];
+    const groupIds = dto.groupIds ?? [];
+    if (userIds.length === 0 && groupIds.length === 0) {
+      return;
+    }
+
+    await this.db.transaction().execute(async (trx) => {
+      let pageAccess = await this.pagePermissionRepo.findPageAccessByPageId(
+        page.id,
+        trx,
+      );
+      // Auto-promote to restricted on first add — matches the Notion-like
+      // affordance "share with X = make it restricted".
+      if (!pageAccess) {
+        pageAccess = await this.pagePermissionRepo.insertPageAccess(
+          {
+            pageId: page.id,
+            workspaceId: page.workspaceId,
+            spaceId: page.spaceId,
+            accessLevel: PageAccessLevel.RESTRICTED,
+            creatorId: user.id,
+          },
+          trx,
+        );
+      }
+
+      const newRows = [
+        ...userIds.map((uid) => ({
+          pageAccessId: pageAccess!.id,
+          userId: uid,
+          role: dto.role,
+          addedById: user.id,
+        })),
+        ...groupIds.map((gid) => ({
+          pageAccessId: pageAccess!.id,
+          groupId: gid,
+          role: dto.role,
+          addedById: user.id,
+        })),
+      ];
+
+      // Drop any existing rows for the same (pageAccess, user/group) so the
+      // insert is idempotent and the role is updated on re-add.
+      if (userIds.length > 0) {
+        await this.pagePermissionRepo.deletePagePermissionsByUserIds(
+          pageAccess!.id,
+          userIds,
+          trx,
+        );
+      }
+      if (groupIds.length > 0) {
+        await this.pagePermissionRepo.deletePagePermissionsByGroupIds(
+          pageAccess!.id,
+          groupIds,
+          trx,
+        );
+      }
+      await this.pagePermissionRepo.insertPagePermissions(newRows, trx);
+    });
+  }
+
+  async removePermissions(
+    dto: RemovePagePermissionDto,
+    user: User,
+  ): Promise<void> {
+    const page = await this.loadPageOrThrow(dto.pageId);
+    await this.pageAccessService.validateCanEdit(page, user);
+
+    const pageAccess = await this.pagePermissionRepo.findPageAccessByPageId(
+      page.id,
+    );
+    if (!pageAccess) return;
+
+    if (dto.userIds && dto.userIds.length > 0) {
+      await this.pagePermissionRepo.deletePagePermissionsByUserIds(
+        pageAccess.id,
+        dto.userIds,
+      );
+    }
+    if (dto.groupIds && dto.groupIds.length > 0) {
+      await this.pagePermissionRepo.deletePagePermissionsByGroupIds(
+        pageAccess.id,
+        dto.groupIds,
+      );
+    }
+  }
+
+  async updatePermissionRole(
+    dto: UpdatePagePermissionDto,
+    user: User,
+  ): Promise<void> {
+    const page = await this.loadPageOrThrow(dto.pageId);
+    await this.pageAccessService.validateCanEdit(page, user);
+
+    const pageAccess = await this.pagePermissionRepo.findPageAccessByPageId(
+      page.id,
+    );
+    if (!pageAccess) {
+      throw new NotFoundException('Page is not restricted');
+    }
+
+    if (!dto.userId && !dto.groupId) {
+      throw new ForbiddenException('userId or groupId required');
+    }
+
+    // Guard against demoting the last writer to reader (locks out everyone).
+    if (dto.role === PagePermissionRole.READER) {
+      const writers = await this.pagePermissionRepo.countWritersByPageAccessId(
+        pageAccess.id,
+      );
+      const target = dto.userId
+        ? await this.pagePermissionRepo.findPagePermissionByUserId(
+            pageAccess.id,
+            dto.userId,
+          )
+        : await this.pagePermissionRepo.findPagePermissionByGroupId(
+            pageAccess.id,
+            dto.groupId!,
+          );
+      if (
+        writers <= 1 &&
+        target?.role === PagePermissionRole.WRITER
+      ) {
+        throw new ForbiddenException(
+          'Cannot demote the last writer of a restricted page',
+        );
+      }
+    }
+
+    await this.pagePermissionRepo.updatePagePermissionRole(
+      pageAccess.id,
+      dto.role,
+      { userId: dto.userId, groupId: dto.groupId },
+    );
+  }
+
+  async listPermissions(
+    pageId: string,
+    user: User,
+    pagination: { limit: number; cursor?: string; query?: string },
+  ) {
+    const page = await this.loadPageOrThrow(pageId);
+    // Only people who can view the page can see who has access.
+    await this.pageAccessService.validateCanView(page, user);
+
+    const pageAccess = await this.pagePermissionRepo.findPageAccessByPageId(
+      page.id,
+    );
+    if (!pageAccess) {
+      return { items: [], meta: { hasNextPage: false, hasPrevPage: false } };
+    }
+    return this.pagePermissionRepo.getPagePermissionsPaginated(
+      pageAccess.id,
+      pagination as any,
+    );
+  }
+
+  async getRestrictionInfo(
+    pageId: string,
+    user: User,
+  ): Promise<RestrictionInfo> {
+    const page = await this.loadPageOrThrow(pageId);
+    await this.pageAccessService.validateCanView(page, user);
+
+    const direct = await this.pagePermissionRepo.findPageAccessByPageId(
+      page.id,
+    );
+    const ancestor = await this.pagePermissionRepo.findRestrictedAncestor(
+      page.id,
+    );
+    // findRestrictedAncestor returns the SAME page when the page itself is
+    // restricted (depth=0). We only consider it "inherited" when depth > 0.
+    const isInherited =
+      !!ancestor && ancestor.depth > 0 && ancestor.pageId !== page.id;
+    const inheritedPage = isInherited
+      ? await this.pageRepo.findById(ancestor!.pageId)
+      : undefined;
+
+    const { hasAnyRestriction, canAccess, canEdit } =
+      await this.pagePermissionRepo.canUserEditPage(user.id, page.id);
+
+    return {
+      restrictionId: direct?.id,
+      hasDirectRestriction: !!direct,
+      hasInheritedRestriction: isInherited,
+      inheritedFrom: inheritedPage
+        ? {
+            id: inheritedPage.id,
+            slugId: inheritedPage.slugId,
+            title: inheritedPage.title ?? '',
+          }
+        : undefined,
+      userAccess: {
+        canView: hasAnyRestriction ? canAccess : true,
+        canEdit: hasAnyRestriction ? canEdit : true,
+        // For now: anyone who can edit can manage permissions. Mirrors the
+        // service-level rule used by addPermissions/restrict.
+        canManage: hasAnyRestriction ? canEdit : true,
+      },
+    };
+  }
+}
diff --git a/apps/server/src/core/page/page.module.ts b/apps/server/src/core/page/page.module.ts
index a2042279..f2e54739 100644
--- a/apps/server/src/core/page/page.module.ts
+++ b/apps/server/src/core/page/page.module.ts
@@ -6,10 +6,17 @@ import { TrashCleanupService } from './services/trash-cleanup.service';
 import { StorageModule } from '../../integrations/storage/storage.module';
 import { CollaborationModule } from '../../collaboration/collaboration.module';
 import { WatcherModule } from '../watcher/watcher.module';
+import { PagePermissionController } from './page-permission/page-permission.controller';
+import { PagePermissionService } from './page-permission/page-permission.service';
 
 @Module({
-  controllers: [PageController],
-  providers: [PageService, PageHistoryService, TrashCleanupService],
+  controllers: [PageController, PagePermissionController],
+  providers: [
+    PageService,
+    PageHistoryService,
+    TrashCleanupService,
+    PagePermissionService,
+  ],
   exports: [PageService, PageHistoryService],
   imports: [StorageModule, CollaborationModule, WatcherModule],
 })
diff --git a/apps/server/src/integrations/environment/license-check.service.ts b/apps/server/src/integrations/environment/license-check.service.ts
index 35c2295a..82071fb7 100644
--- a/apps/server/src/integrations/environment/license-check.service.ts
+++ b/apps/server/src/integrations/environment/license-check.service.ts
@@ -1,6 +1,21 @@
 import { Injectable } from '@nestjs/common';
 import { ModuleRef } from '@nestjs/core';
 import { EnvironmentService } from './environment.service';
+import { Feature } from '../../common/features';
+
+/**
+ * Acadenice — features OSS-ifiees inconditionnellement (open-source).
+ * Toujours injectees dans la reponse `resolveFeatures` quel que soit le plan
+ * ou la license. Permet de garder le pipeline `useHasFeature(...)` cote front
+ * et les guards cote serveur sans toucher au flux EE.
+ *
+ * Why: reproduit la logique du Patch 020 (branding) et R4.5 (audit, api-keys)
+ * appliques par overrides UI directs. Centralise ici pour rester DRY.
+ */
+const ACADENICE_OSS_FEATURES: ReadonlyArray<string> = [
+  Feature.PAGE_PERMISSIONS,
+  Feature.SHARING_CONTROLS,
+];
 
 @Injectable()
 export class LicenseCheckService {
@@ -27,6 +42,9 @@ export class LicenseCheckService {
   }
 
   hasFeature(licenseKey: string, feature: string, plan?: string): boolean {
+    if (ACADENICE_OSS_FEATURES.includes(feature)) {
+      return true;
+    }
     if (this.environmentService.isCloud()) {
       try {
         // eslint-disable-next-line @typescript-eslint/no-require-imports
@@ -63,17 +81,22 @@ export class LicenseCheckService {
   }
 
   resolveFeatures(licenseKey: string, plan: string): string[] {
+    let base: string[];
     if (this.environmentService.isCloud()) {
       try {
         // eslint-disable-next-line @typescript-eslint/no-require-imports
         const { getFeaturesForCloudPlan } = require('../../ee/licence/feature-registry');
-        return [...getFeaturesForCloudPlan(plan)];
+        base = [...getFeaturesForCloudPlan(plan)];
       } catch {
-        return [];
+        base = [];
       }
+    } else {
+      base = this.getFeatures(licenseKey);
     }
-
-    return this.getFeatures(licenseKey);
+    // Inject Acadenice OSS-ified features unconditionally.
+    const set = new Set(base);
+    for (const f of ACADENICE_OSS_FEATURES) set.add(f);
+    return [...set];
   }
 
   resolveTier(licenseKey: string, plan: string): string {
diff --git a/apps/server/tsconfig.build.json b/apps/server/tsconfig.build.json
index ecb7f40d..42a7a2f1 100644
--- a/apps/server/tsconfig.build.json
+++ b/apps/server/tsconfig.build.json
@@ -1,5 +1,5 @@
 {
   "extends": "./tsconfig.json",
   "exclude": ["node_modules",
-    "test", "dist", "**/*spec.ts"]
+    "test", "dist", "**/*spec.ts", "vitest.config.ts"]
 }