diff --git a/SPARC/api.py b/SPARC/api.py
index b6095bd..d380e1d 100644
--- a/SPARC/api.py
+++ b/SPARC/api.py
@@ -474,11 +474,46 @@ class TrackCompanyRequest(BaseModel):
     company_name: CompanyName = Field(...)
 
 
+@app.get("/tracked", tags=["Tracked Companies"])
+async def list_my_tracked_companies(
+    current_user: UserResponse = Depends(get_current_user),
+):
+    """List tracked companies for the current user."""
+    db = get_db_client()
+    return db.list_tracked_companies(owner_id=current_user.id)
+
+
+@app.post("/tracked", tags=["Tracked Companies"])
+async def add_my_tracked_company(
+    request: TrackCompanyRequest,
+    current_user: UserResponse = Depends(get_current_user),
+):
+    """Add a company to the current user's tracked list."""
+    db = get_db_client()
+    result = db.add_tracked_company(request.company_name, owner_id=current_user.id)
+    if not result:
+        raise HTTPException(status_code=409, detail="Company already tracked")
+    return result
+
+
+@app.delete("/tracked/{company_name}", tags=["Tracked Companies"])
+async def remove_my_tracked_company(
+    company_name: Annotated[str, Path(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$")],
+    current_user: UserResponse = Depends(get_current_user),
+):
+    """Remove a company from the current user's tracked list."""
+    db = get_db_client()
+    removed = db.remove_tracked_company(company_name, owner_id=current_user.id)
+    if not removed:
+        raise HTTPException(status_code=404, detail="Company not found in tracking list")
+    return {"message": f"Stopped tracking {company_name}"}
+
+
 @app.get("/admin/tracked", tags=["Admin"])
 async def list_tracked_companies(
     _: UserResponse = Depends(get_current_admin),
 ):
-    """List all tracked companies (admin only)."""
+    """List all tracked companies across all users (admin only)."""
     db = get_db_client()
     return db.list_tracked_companies()
 
@@ -486,11 +521,11 @@ async def list_tracked_companies(
 @app.post("/admin/tracked", tags=["Admin"])
 async def add_tracked_company(
     request: TrackCompanyRequest,
-    _: UserResponse = Depends(get_current_admin),
+    current_admin: UserResponse = Depends(get_current_admin),
 ):
-    """Add a company to the tracked list (admin only)."""
+    """Add a company to the tracked list (admin only, owned by admin)."""
     db = get_db_client()
-    result = db.add_tracked_company(request.company_name)
+    result = db.add_tracked_company(request.company_name, owner_id=current_admin.id)
     if not result:
         raise HTTPException(status_code=409, detail="Company already tracked")
     return result
@@ -501,7 +536,7 @@ async def remove_tracked_company(
     company_name: Annotated[str, Path(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$")],
     _: UserResponse = Depends(get_current_admin),
 ):
-    """Remove a company from the tracked list (admin only)."""
+    """Remove a company from the tracked list (admin only, any owner)."""
     db = get_db_client()
     removed = db.remove_tracked_company(company_name)
     if not removed:
@@ -582,17 +617,86 @@ async def list_alerts(
     return db.list_alerts(limit=limit)
 
 
+# ============== Admin-Scoped Data Endpoints ==============
+
+
+@app.get("/admin/analyses", response_model=PaginatedAnalysisResponse, tags=["Admin"])
+async def admin_list_analyses(
+    company_name: Annotated[
+        str | None,
+        Query(description="Filter results by company name"),
+    ] = None,
+    limit: Annotated[int, Query(ge=1, le=200)] = 50,
+    cursor: Annotated[
+        str | None,
+        Query(description="Opaque cursor from a previous response's next_cursor field"),
+    ] = None,
+    _: UserResponse = Depends(get_current_admin),
+):
+    """List all analysis results across all users (admin only)."""
+    db = _get_job_db()
+    rows = db.list_analyses(company_name=company_name, limit=limit + 1, cursor=cursor)
+
+    has_next = len(rows) > limit
+    if has_next:
+        rows = rows[:limit]
+
+    items = [AnalysisRecord(**row) for row in rows]
+
+    next_cursor = None
+    if has_next and rows:
+        last = rows[-1]
+        ts = last["timestamp"]
+        ts_str = ts.isoformat() if hasattr(ts, "isoformat") else str(ts)
+        next_cursor = f"{ts_str}|{last['id']}"
+
+    return PaginatedAnalysisResponse(items=items, next_cursor=next_cursor)
+
+
+@app.get("/admin/jobs", response_model=PaginatedJobsResponse, tags=["Admin"])
+async def admin_list_jobs(
+    status: Annotated[
+        str | None,
+        Query(description="Filter by status: pending, running, completed, failed"),
+    ] = None,
+    limit: Annotated[int, Query(ge=1, le=200)] = 50,
+    cursor: Annotated[
+        str | None,
+        Query(description="Opaque cursor from a previous response's next_cursor field"),
+    ] = None,
+    _: UserResponse = Depends(get_current_admin),
+):
+    """List all jobs across all users (admin only)."""
+    db = _get_job_db()
+    job_rows = db.list_jobs(status=status, limit=limit + 1, cursor=cursor)
+
+    has_next = len(job_rows) > limit
+    if has_next:
+        job_rows = job_rows[:limit]
+
+    items = [_job_row_to_status(row) for row in job_rows]
+
+    next_cursor = None
+    if has_next and job_rows:
+        last = job_rows[-1]
+        created = last["created_at"]
+        ts = created.isoformat() if hasattr(created, "isoformat") else str(created)
+        next_cursor = f"{ts}|{last['job_id']}"
+
+    return PaginatedJobsResponse(items=items, next_cursor=next_cursor)
+
+
 # ============== Analytics Endpoint ==============
 
 
 @app.get("/analytics", response_model=AnalyticsResponse, tags=["Analytics"])
 async def get_analytics(
     days: int = Query(default=30, ge=1, le=365),
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """Get analytics data (authenticated users only)."""
+    """Get analytics data scoped to the current user."""
     db = get_db_client()
-    analytics = db.get_analytics(days=days)
+    analytics = db.get_analytics(days=days, owner_id=current_user.id)
 
     return AnalyticsResponse(
         total_messages=analytics["total_messages"],
@@ -645,9 +749,9 @@ async def list_models():
 @app.get("/analytics/trends", tags=["Analytics"])
 async def get_analytics_trends(
     days: int = Query(default=90, ge=7, le=365),
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """Get trend data for patent analysis over time.
+    """Get trend data for patent analysis over time (scoped to current user).
 
     Returns two datasets:
     - ``by_month``: analysis count per company per month
@@ -661,11 +765,14 @@ async def get_analytics_trends(
     """
     db = get_db_client()
 
+    owner_filter = " AND owner_id = %s" if current_user else ""
+    owner_params = (current_user.id,) if current_user else ()
+
     with db.get_conn() as conn:
         with conn.cursor() as cur:
             # Analyses per company per month
             cur.execute(
-                """
+                f"""
                 SELECT
                     TO_CHAR(timestamp, 'YYYY-MM') AS month,
                     company_name,
@@ -674,16 +781,17 @@ async def get_analytics_trends(
                 WHERE timestamp >= NOW() - INTERVAL '%s days'
                     AND is_cached = FALSE
                     AND company_name IS NOT NULL
+                    {owner_filter}
                 GROUP BY month, company_name
                 ORDER BY month
                 """,
-                (days,),
+                (days, *owner_params),
             )
             by_month_rows = cur.fetchall()
 
             # Analysis type distribution per month
             cur.execute(
-                """
+                f"""
                 SELECT
                     TO_CHAR(timestamp, 'YYYY-MM') AS month,
                     analysis_type,
@@ -691,10 +799,11 @@ async def get_analytics_trends(
                 FROM llm_messages
                 WHERE timestamp >= NOW() - INTERVAL '%s days'
                     AND is_cached = FALSE
+                    {owner_filter}
                 GROUP BY month, analysis_type
                 ORDER BY month
                 """,
-                (days,),
+                (days, *owner_params),
             )
             by_type_rows = cur.fetchall()
 
@@ -720,9 +829,9 @@ async def get_analytics_trends(
 @app.get("/export/{company_name}", tags=["Export"])
 async def export_company_csv(
     company_name: Annotated[str, Path(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$")],
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """Export analysis results for a company as a CSV file.
+    """Export analysis results for a company as a CSV file (scoped to current user).
 
     Returns all stored analysis records for the given company, including
     analysis type, model used, response text, and timestamp.
@@ -737,7 +846,7 @@ async def export_company_csv(
     import io
 
     db = get_db_client()
-    # Query all non-cached analysis results for this company
+    # Query all non-cached analysis results for this company owned by current user
     with db.get_conn() as conn:
         with conn.cursor() as cur:
             cur.execute(
@@ -745,9 +854,10 @@ async def export_company_csv(
                 SELECT company_name, analysis_type, model, response, timestamp
                 FROM llm_messages
                 WHERE LOWER(company_name) = LOWER(%s) AND is_cached = FALSE
+                    AND owner_id = %s
                 ORDER BY timestamp DESC
                 """,
-                (company_name,),
+                (company_name, current_user.id),
             )
             rows = cur.fetchall()
 
@@ -772,9 +882,9 @@ async def export_company_csv(
 @app.get("/export/{company_name}/pdf", tags=["Export"])
 async def export_company_pdf(
     company_name: Annotated[str, Path(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$")],
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """Export analysis results for a company as a formatted PDF report.
+    """Export analysis results for a company as a formatted PDF report (scoped to current user).
 
     Returns all stored analysis records for the given company, including
     analysis type, model used, response text, and timestamp, formatted
@@ -808,9 +918,10 @@ async def export_company_pdf(
                 SELECT company_name, analysis_type, model, response, timestamp
                 FROM llm_messages
                 WHERE LOWER(company_name) = LOWER(%s) AND is_cached = FALSE
+                    AND owner_id = %s
                 ORDER BY timestamp DESC
                 """,
-                (company_name,),
+                (company_name, current_user.id),
             )
             rows = cur.fetchall()
 
@@ -939,68 +1050,6 @@ async def health_check():
     )
 
 
-@app.get(
-    "/analyze/{company_name}",
-    response_model=CompanyAnalysisResponse,
-    tags=["Analysis"],
-)
-async def analyze_company(
-    company_name: Annotated[str, Path(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$")],
-    model: str | None = Query(default=None, description="LLM model to use (e.g. 'openai/gpt-4o'). Defaults to server config."),
-    _: UserResponse = Depends(get_current_user),
-):
-    """Analyze a single company's patent portfolio.
-
-    This endpoint retrieves recent patents for the specified company,
-    parses them, and uses AI to generate a comprehensive analysis.
-
-    Args:
-        company_name: Name of the company to analyze (e.g., "nvidia", "intel")
-        model: Optional LLM model override
-
-    Returns:
-        Analysis results including patent count, AI insights, and success status
-    """
-    _validate_model(model)
-    if not _analyzer:
-        raise HTTPException(status_code=503, detail="Analyzer not initialized")
-
-    result = _analyzer._analyze_company_safe(company_name, model=model)
-    return _convert_result(result)
-
-
-@app.get(
-    "/analyze/patent/{patent_id}",
-    tags=["Analysis"],
-)
-async def analyze_single_patent(
-    patent_id: str,
-    company_name: Annotated[str, Query(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$", description="Company name for analysis context")],
-    _: UserResponse = Depends(get_current_user),
-):
-    """Analyze a single patent by its publication ID.
-
-    If the patent PDF is not already cached locally, the system will attempt
-    to download it automatically from a previously cached link. If no link
-    is available, a 404 error is returned.
-
-    Args:
-        patent_id: Patent publication ID (e.g. "US-11234567-B2")
-        company_name: Company name for analysis context
-
-    Returns:
-        Analysis text for the patent
-    """
-    if not _analyzer:
-        raise HTTPException(status_code=503, detail="Analyzer not initialized")
-
-    try:
-        analysis = _analyzer.analyze_single_patent(patent_id, company_name)
-        return {"patent_id": patent_id, "company_name": company_name, "analysis": analysis}
-    except FileNotFoundError as e:
-        raise HTTPException(status_code=404, detail=str(e))
-
-
 @app.get(
     "/analyze/batch",
     response_model=PaginatedAnalysisResponse,
@@ -1016,9 +1065,9 @@ async def list_analysis_results(
         str | None,
         Query(description="Opaque cursor from a previous response's next_cursor field"),
     ] = None,
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """List stored analysis results with cursor-based pagination.
+    """List stored analysis results with cursor-based pagination (scoped to current user).
 
     Returns past analysis results ordered by timestamp descending. Use
     ``limit`` to control page size (default 50, max 200). The response
@@ -1035,7 +1084,7 @@ async def list_analysis_results(
         Paginated list of analysis results
     """
     db = _get_job_db()
-    rows = db.list_analyses(company_name=company_name, limit=limit + 1, cursor=cursor)
+    rows = db.list_analyses(company_name=company_name, limit=limit + 1, cursor=cursor, owner_id=current_user.id)
 
     has_next = len(rows) > limit
     if has_next:
@@ -1085,6 +1134,68 @@ async def analyze_companies_batch(
     return _convert_batch_result(result)
 
 
+@app.get(
+    "/analyze/patent/{patent_id}",
+    tags=["Analysis"],
+)
+async def analyze_single_patent(
+    patent_id: str,
+    company_name: Annotated[str, Query(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$", description="Company name for analysis context")],
+    _: UserResponse = Depends(get_current_user),
+):
+    """Analyze a single patent by its publication ID.
+
+    If the patent PDF is not already cached locally, the system will attempt
+    to download it automatically from a previously cached link. If no link
+    is available, a 404 error is returned.
+
+    Args:
+        patent_id: Patent publication ID (e.g. "US-11234567-B2")
+        company_name: Company name for analysis context
+
+    Returns:
+        Analysis text for the patent
+    """
+    if not _analyzer:
+        raise HTTPException(status_code=503, detail="Analyzer not initialized")
+
+    try:
+        analysis = _analyzer.analyze_single_patent(patent_id, company_name)
+        return {"patent_id": patent_id, "company_name": company_name, "analysis": analysis}
+    except FileNotFoundError as e:
+        raise HTTPException(status_code=404, detail=str(e))
+
+
+@app.get(
+    "/analyze/{company_name}",
+    response_model=CompanyAnalysisResponse,
+    tags=["Analysis"],
+)
+async def analyze_company(
+    company_name: Annotated[str, Path(min_length=2, max_length=100, pattern=r"^[a-zA-Z0-9][a-zA-Z0-9 \-&.]*$")],
+    model: str | None = Query(default=None, description="LLM model to use (e.g. 'openai/gpt-4o'). Defaults to server config."),
+    _: UserResponse = Depends(get_current_user),
+):
+    """Analyze a single company's patent portfolio.
+
+    This endpoint retrieves recent patents for the specified company,
+    parses them, and uses AI to generate a comprehensive analysis.
+
+    Args:
+        company_name: Name of the company to analyze (e.g., "nvidia", "intel")
+        model: Optional LLM model override
+
+    Returns:
+        Analysis results including patent count, AI insights, and success status
+    """
+    _validate_model(model)
+    if not _analyzer:
+        raise HTTPException(status_code=503, detail="Analyzer not initialized")
+
+    result = _analyzer._analyze_company_safe(company_name, model=model)
+    return _convert_result(result)
+
+
 def _get_job_db() -> "DatabaseClient":
     """Get a DatabaseClient for job persistence."""
     from SPARC.database import DatabaseClient
@@ -1171,7 +1282,7 @@ def _run_batch_job(job_id: str, companies: list[str], max_workers: int, model: s
 async def analyze_companies_async(
     request: BatchAnalysisRequest,
     background_tasks: BackgroundTasks,
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
     """Start an asynchronous batch analysis job.
 
@@ -1191,7 +1302,7 @@ async def analyze_companies_async(
     job_id = f"job_{_job_counter}_{datetime.now().strftime('%Y%m%d%H%M%S')}"
 
     db = _get_job_db()
-    job_row = db.create_job(job_id=job_id, total_companies=len(request.companies))
+    job_row = db.create_job(job_id=job_id, total_companies=len(request.companies), owner_id=current_user.id)
 
     background_tasks.add_task(
         _run_batch_job, job_id, request.companies, request.max_workers, request.model
@@ -1203,9 +1314,9 @@ async def analyze_companies_async(
 @app.get("/jobs/{job_id}", response_model=JobStatus, tags=["Jobs"])
 async def get_job_status(
     job_id: str,
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """Get the status of a background analysis job.
+    """Get the status of a background analysis job (scoped to current user).
 
     Args:
         job_id: The job ID returned from the async batch endpoint
@@ -1214,7 +1325,7 @@ async def get_job_status(
         Current job status including progress and results when complete
     """
     db = _get_job_db()
-    job_row = db.get_job(job_id)
+    job_row = db.get_job(job_id, owner_id=current_user.id)
 
     if not job_row:
         raise HTTPException(status_code=404, detail=f"Job {job_id} not found")
@@ -1233,9 +1344,9 @@ async def list_jobs(
         str | None,
         Query(description="Opaque cursor from a previous response's next_cursor field"),
     ] = None,
-    _: UserResponse = Depends(get_current_user),
+    current_user: UserResponse = Depends(get_current_user),
 ):
-    """List analysis jobs with cursor-based pagination.
+    """List analysis jobs with cursor-based pagination (scoped to current user).
 
     Pass ``limit`` to control page size. The response includes a ``next_cursor``
     field; pass it back as the ``cursor`` query parameter to fetch the next page.
@@ -1254,7 +1365,7 @@ async def list_jobs(
     """
     db = _get_job_db()
     # Fetch one extra to determine if there is a next page
-    job_rows = db.list_jobs(status=status, limit=limit + 1, cursor=cursor)
+    job_rows = db.list_jobs(status=status, limit=limit + 1, cursor=cursor, owner_id=current_user.id)
 
     has_next = len(job_rows) > limit
     if has_next:
diff --git a/SPARC/database.py b/SPARC/database.py
index 0759a66..a393162 100644
--- a/SPARC/database.py
+++ b/SPARC/database.py
@@ -196,7 +196,7 @@ class DatabaseClient:
             cursor.execute("""
                 CREATE TABLE IF NOT EXISTS tracked_companies (
                     id SERIAL PRIMARY KEY,
-                    company_name VARCHAR(255) UNIQUE NOT NULL,
+                    company_name VARCHAR(255) NOT NULL,
                     last_patent_count INTEGER DEFAULT 0,
                     last_analysis_at TIMESTAMP,
                     created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
@@ -221,6 +221,68 @@ class DatabaseClient:
                 ON alerts(company_name)
             """)
 
+            # ---- Multi-tenant: add owner_id columns if missing ----
+            cursor.execute("""
+                DO $$
+                BEGIN
+                    -- llm_messages.owner_id
+                    IF NOT EXISTS (
+                        SELECT 1 FROM information_schema.columns
+                        WHERE table_name = 'llm_messages' AND column_name = 'owner_id'
+                    ) THEN
+                        ALTER TABLE llm_messages ADD COLUMN owner_id INTEGER REFERENCES users(id);
+                    END IF;
+                    -- jobs.owner_id
+                    IF NOT EXISTS (
+                        SELECT 1 FROM information_schema.columns
+                        WHERE table_name = 'jobs' AND column_name = 'owner_id'
+                    ) THEN
+                        ALTER TABLE jobs ADD COLUMN owner_id INTEGER REFERENCES users(id);
+                    END IF;
+                    -- tracked_companies.owner_id
+                    IF NOT EXISTS (
+                        SELECT 1 FROM information_schema.columns
+                        WHERE table_name = 'tracked_companies' AND column_name = 'owner_id'
+                    ) THEN
+                        ALTER TABLE tracked_companies ADD COLUMN owner_id INTEGER REFERENCES users(id);
+                    END IF;
+                END $$;
+            """)
+
+            # Indexes for owner_id filtering
+            cursor.execute("""
+                CREATE INDEX IF NOT EXISTS idx_messages_owner
+                ON llm_messages(owner_id)
+            """)
+            cursor.execute("""
+                CREATE INDEX IF NOT EXISTS idx_jobs_owner
+                ON jobs(owner_id)
+            """)
+            cursor.execute("""
+                CREATE INDEX IF NOT EXISTS idx_tracked_companies_owner
+                ON tracked_companies(owner_id)
+            """)
+
+            # Drop the old unique constraint on company_name alone (if it exists)
+            # and replace with a per-owner unique constraint so different users
+            # can track the same company independently.
+            cursor.execute("""
+                DO $$
+                BEGIN
+                    IF EXISTS (
+                        SELECT 1 FROM pg_constraint
+                        WHERE conname = 'tracked_companies_company_name_key'
+                    ) THEN
+                        ALTER TABLE tracked_companies
+                            DROP CONSTRAINT tracked_companies_company_name_key;
+                    END IF;
+                END $$;
+            """)
+            cursor.execute("""
+                CREATE UNIQUE INDEX IF NOT EXISTS uq_tracked_company_owner
+                ON tracked_companies(LOWER(company_name), owner_id)
+            """)
+
             self.conn.commit()
 
     @staticmethod
@@ -289,6 +351,7 @@ class DatabaseClient:
         metadata: Optional[Dict] = None,
         token_usage: Optional[Dict] = None,
         is_cached: bool = False,
+        owner_id: Optional[int] = None,
     ) -> int:
         """Store an LLM message exchange in the database.
 
@@ -301,6 +364,7 @@ class DatabaseClient:
             metadata: Additional metadata as dict
             token_usage: Token usage information
             is_cached: Whether this response was served from cache
+            owner_id: ID of the user who owns this record
 
         Returns:
             The ID of the inserted record
@@ -312,8 +376,8 @@ class DatabaseClient:
                 cursor.execute(
                     """
                     INSERT INTO llm_messages
-                    (prompt, prompt_hash, response, company_name, analysis_type, model, metadata, token_usage, is_cached)
-                    VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s)
+                    (prompt, prompt_hash, response, company_name, analysis_type, model, metadata, token_usage, is_cached, owner_id)
+                    VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
                     RETURNING id
                     """,
                     (
@@ -326,6 +390,7 @@ class DatabaseClient:
                         json.dumps(metadata) if metadata else None,
                         json.dumps(token_usage) if token_usage else None,
                         is_cached,
+                        owner_id,
                     ),
                 )
 
@@ -340,6 +405,7 @@ class DatabaseClient:
         analysis_type: Optional[str] = None,
         limit: int = 100,
         offset: int = 0,
+        owner_id: Optional[int] = None,
     ) -> List[Dict]:
         """Retrieve messages from the database.
 
@@ -348,6 +414,7 @@ class DatabaseClient:
             analysis_type: Filter by analysis type
             limit: Maximum number of records to return
             offset: Number of records to skip
+            owner_id: Filter by owner (None returns all, for admin use)
 
         Returns:
             List of message dictionaries
@@ -355,6 +422,10 @@ class DatabaseClient:
         query = "SELECT * FROM llm_messages WHERE 1=1"
         params = []
 
+        if owner_id is not None:
+            query += " AND owner_id = %s"
+            params.append(owner_id)
+
         if company_name:
             query += " AND company_name = %s"
             params.append(company_name)
@@ -376,6 +447,7 @@ class DatabaseClient:
         company_name: Optional[str] = None,
         limit: int = 50,
         cursor: Optional[str] = None,
+        owner_id: Optional[int] = None,
     ) -> List[Dict]:
         """List analysis results with cursor-based pagination.
 
@@ -383,6 +455,7 @@ class DatabaseClient:
             company_name: Optional filter by company name.
             limit: Maximum number of records to return.
             cursor: Opaque cursor (``timestamp|id``) from a previous response.
+            owner_id: Filter by owner (None returns all, for admin use).
 
         Returns:
             List of analysis dicts ordered by timestamp descending.
@@ -390,6 +463,10 @@ class DatabaseClient:
         conditions: list[str] = ["is_cached = FALSE"]
         params: list = []
 
+        if owner_id is not None:
+            conditions.append("owner_id = %s")
+            params.append(owner_id)
+
         if company_name:
             conditions.append("LOWER(company_name) = LOWER(%s)")
             params.append(company_name)
@@ -413,52 +490,62 @@ class DatabaseClient:
                 cur.execute(query, params)
                 return [dict(row) for row in cur.fetchall()]
 
-    def get_analytics(self, days: int = 30) -> Dict:
+    def get_analytics(self, days: int = 30, owner_id: Optional[int] = None) -> Dict:
         """Get analytics on message usage.
 
         Args:
             days: Number of days to look back
+            owner_id: Filter by owner (None returns all, for admin use)
 
         Returns:
             Dictionary with analytics data
         """
+        owner_filter = ""
+        owner_params: list = []
+        if owner_id is not None:
+            owner_filter = " AND owner_id = %s"
+            owner_params = [owner_id]
+
         with self.get_conn() as conn:
             with conn.cursor(cursor_factory=RealDictCursor) as cursor:
                 # Total messages
                 cursor.execute(
-                    """
+                    f"""
                     SELECT COUNT(*) as total_messages
                     FROM llm_messages
                     WHERE timestamp >= NOW() - INTERVAL '%s days'
+                    {owner_filter}
                     """,
-                    (days,),
+                    (days, *owner_params),
                 )
                 total = cursor.fetchone()["total_messages"]
 
                 # Messages by company
                 cursor.execute(
-                    """
+                    f"""
                     SELECT company_name, COUNT(*) as count
                     FROM llm_messages
                     WHERE timestamp >= NOW() - INTERVAL '%s days'
+                    {owner_filter}
                     GROUP BY company_name
                     ORDER BY count DESC
                     LIMIT 10
                     """,
-                    (days,),
+                    (days, *owner_params),
                 )
                 by_company = cursor.fetchall()
 
                 # Messages by type
                 cursor.execute(
-                    """
+                    f"""
                     SELECT analysis_type, COUNT(*) as count
                     FROM llm_messages
                     WHERE timestamp >= NOW() - INTERVAL '%s days'
+                    {owner_filter}
                     GROUP BY analysis_type
                     ORDER BY count DESC
                     """,
-                    (days,),
+                    (days, *owner_params),
                 )
                 by_type = cursor.fetchall()
 
@@ -556,12 +643,14 @@ class DatabaseClient:
         self,
         job_id: str,
         total_companies: int,
+        owner_id: Optional[int] = None,
     ) -> Dict:
         """Create a new job record.
 
         Args:
             job_id: Unique job identifier
             total_companies: Number of companies in the batch
+            owner_id: ID of the user who owns this job
 
         Returns:
             Job dict
@@ -570,11 +659,11 @@ class DatabaseClient:
             with conn.cursor(cursor_factory=RealDictCursor) as cursor:
                 cursor.execute(
                     """
-                    INSERT INTO jobs (job_id, status, progress, total_companies, completed_companies)
-                    VALUES (%s, 'pending', 0, %s, 0)
+                    INSERT INTO jobs (job_id, status, progress, total_companies, completed_companies, owner_id)
+                    VALUES (%s, 'pending', 0, %s, 0, %s)
                     RETURNING *
                     """,
-                    (job_id, total_companies),
+                    (job_id, total_companies, owner_id),
                 )
                 job = cursor.fetchone()
             conn.commit()
@@ -627,11 +716,22 @@ class DatabaseClient:
             conn.commit()
             return dict(job) if job else None
 
-    def get_job(self, job_id: str) -> Optional[Dict]:
-        """Get a job by ID."""
+    def get_job(self, job_id: str, owner_id: Optional[int] = None) -> Optional[Dict]:
+        """Get a job by ID.
+
+        Args:
+            job_id: Job identifier.
+            owner_id: When provided, only return the job if it belongs to this owner.
+        """
+        query = "SELECT * FROM jobs WHERE job_id = %s"
+        params: list = [job_id]
+        if owner_id is not None:
+            query += " AND owner_id = %s"
+            params.append(owner_id)
+
         with self.get_conn() as conn:
             with conn.cursor(cursor_factory=RealDictCursor) as cursor:
-                cursor.execute("SELECT * FROM jobs WHERE job_id = %s", (job_id,))
+                cursor.execute(query, params)
                 job = cursor.fetchone()
                 return dict(job) if job else None
 
@@ -640,6 +740,7 @@ class DatabaseClient:
         status: Optional[str] = None,
         limit: int = 10,
         cursor: Optional[str] = None,
+        owner_id: Optional[int] = None,
     ) -> List[Dict]:
         """List jobs with optional status filter and cursor-based pagination.
 
@@ -649,6 +750,7 @@ class DatabaseClient:
             cursor: Opaque cursor (``created_at|job_id``) from a previous
                 response. When provided, only jobs older than the cursor are
                 returned.
+            owner_id: Filter by owner (None returns all, for admin use).
 
         Returns:
             List of job dicts ordered by created_at descending.
@@ -656,6 +758,10 @@ class DatabaseClient:
         conditions: list[str] = []
         params: list = []
 
+        if owner_id is not None:
+            conditions.append("owner_id = %s")
+            params.append(owner_id)
+
         if status:
             conditions.append("status = %s")
             params.append(status)
@@ -902,14 +1008,21 @@ class DatabaseClient:
 
     # Tracked Companies Methods
 
-    def add_tracked_company(self, company_name: str) -> Optional[Dict]:
-        """Add a company to the tracking list."""
+    def add_tracked_company(
+        self, company_name: str, owner_id: Optional[int] = None
+    ) -> Optional[Dict]:
+        """Add a company to the tracking list.
+
+        Args:
+            company_name: Company name to track.
+            owner_id: ID of the user who owns this tracked company.
+        """
         with self.get_conn() as conn:
             with conn.cursor(cursor_factory=RealDictCursor) as cursor:
                 try:
                     cursor.execute(
-                        "INSERT INTO tracked_companies (company_name) VALUES (%s) RETURNING *",
-                        (company_name,),
+                        "INSERT INTO tracked_companies (company_name, owner_id) VALUES (%s, %s) RETURNING *",
+                        (company_name, owner_id),
                     )
                     row = cursor.fetchone()
                     conn.commit()
@@ -918,22 +1031,45 @@ class DatabaseClient:
                     conn.rollback()
                     return None
 
-    def remove_tracked_company(self, company_name: str) -> bool:
-        """Remove a company from the tracking list."""
+    def remove_tracked_company(
+        self, company_name: str, owner_id: Optional[int] = None
+    ) -> bool:
+        """Remove a company from the tracking list.
+
+        Args:
+            company_name: Company name to remove.
+            owner_id: When provided, only remove if owned by this user.
+        """
+        query = "DELETE FROM tracked_companies WHERE LOWER(company_name) = LOWER(%s)"
+        params: list = [company_name]
+        if owner_id is not None:
+            query += " AND owner_id = %s"
+            params.append(owner_id)
+
         with self.get_conn() as conn:
             with conn.cursor() as cursor:
-                cursor.execute(
-                    "DELETE FROM tracked_companies WHERE LOWER(company_name) = LOWER(%s)",
-                    (company_name,),
-                )
+                cursor.execute(query, params)
                 conn.commit()
                 return cursor.rowcount > 0
 
-    def list_tracked_companies(self) -> List[Dict]:
-        """List all tracked companies."""
+    def list_tracked_companies(
+        self, owner_id: Optional[int] = None
+    ) -> List[Dict]:
+        """List tracked companies.
+
+        Args:
+            owner_id: Filter by owner (None returns all, for admin/scheduler use).
+        """
+        query = "SELECT * FROM tracked_companies"
+        params: list = []
+        if owner_id is not None:
+            query += " WHERE owner_id = %s"
+            params.append(owner_id)
+        query += " ORDER BY company_name"
+
         with self.get_conn() as conn:
             with conn.cursor(cursor_factory=RealDictCursor) as cursor:
-                cursor.execute("SELECT * FROM tracked_companies ORDER BY company_name")
+                cursor.execute(query, params)
                 return [dict(row) for row in cursor.fetchall()]
 
     def update_tracked_company(
diff --git a/scripts/migrate_add_owner_id.py b/scripts/migrate_add_owner_id.py
new file mode 100644
index 0000000..3e0ea53
--- /dev/null
+++ b/scripts/migrate_add_owner_id.py
@@ -0,0 +1,132 @@
+#!/usr/bin/env python3
+"""Migration: add owner_id columns and backfill existing rows.
+
+This script adds an ``owner_id`` column (FK to ``users``) to the
+``llm_messages``, ``jobs``, and ``tracked_companies`` tables, then
+backfills all existing rows with ``owner_id = 1`` (the default admin user).
+
+It also replaces the old global UNIQUE constraint on
+``tracked_companies.company_name`` with a per-owner unique index so that
+different users can independently track the same company.
+
+Usage:
+    python scripts/migrate_add_owner_id.py
+
+The script is idempotent — running it multiple times is safe.
+"""
+
+import os
+import sys
+
+import psycopg2
+
+DATABASE_URL = os.getenv(
+    "DATABASE_URL",
+    "postgresql://postgres:postgres@localhost:5432/sparc",
+)
+
+DEFAULT_OWNER_ID = 1
+
+
+def run_migration():
+    """Execute the migration."""
+    conn = psycopg2.connect(DATABASE_URL)
+    conn.autocommit = False
+
+    try:
+        with conn.cursor() as cur:
+            # ---------- 1. Add owner_id columns if missing ----------
+            cur.execute("""
+                DO $$
+                BEGIN
+                    IF NOT EXISTS (
+                        SELECT 1 FROM information_schema.columns
+                        WHERE table_name = 'llm_messages' AND column_name = 'owner_id'
+                    ) THEN
+                        ALTER TABLE llm_messages ADD COLUMN owner_id INTEGER REFERENCES users(id);
+                    END IF;
+
+                    IF NOT EXISTS (
+                        SELECT 1 FROM information_schema.columns
+                        WHERE table_name = 'jobs' AND column_name = 'owner_id'
+                    ) THEN
+                        ALTER TABLE jobs ADD COLUMN owner_id INTEGER REFERENCES users(id);
+                    END IF;
+
+                    IF NOT EXISTS (
+                        SELECT 1 FROM information_schema.columns
+                        WHERE table_name = 'tracked_companies' AND column_name = 'owner_id'
+                    ) THEN
+                        ALTER TABLE tracked_companies ADD COLUMN owner_id INTEGER REFERENCES users(id);
+                    END IF;
+                END $$;
+            """)
+
+            # ---------- 2. Backfill owner_id = DEFAULT_OWNER_ID ----------
+            cur.execute(
+                "UPDATE llm_messages SET owner_id = %s WHERE owner_id IS NULL",
+                (DEFAULT_OWNER_ID,),
+            )
+            messages_updated = cur.rowcount
+            print(f"  llm_messages: backfilled {messages_updated} rows")
+
+            cur.execute(
+                "UPDATE jobs SET owner_id = %s WHERE owner_id IS NULL",
+                (DEFAULT_OWNER_ID,),
+            )
+            jobs_updated = cur.rowcount
+            print(f"  jobs: backfilled {jobs_updated} rows")
+
+            cur.execute(
+                "UPDATE tracked_companies SET owner_id = %s WHERE owner_id IS NULL",
+                (DEFAULT_OWNER_ID,),
+            )
+            tracked_updated = cur.rowcount
+            print(f"  tracked_companies: backfilled {tracked_updated} rows")
+
+            # ---------- 3. Create indexes ----------
+            cur.execute("""
+                CREATE INDEX IF NOT EXISTS idx_messages_owner
+                ON llm_messages(owner_id)
+            """)
+            cur.execute("""
+                CREATE INDEX IF NOT EXISTS idx_jobs_owner
+                ON jobs(owner_id)
+            """)
+            cur.execute("""
+                CREATE INDEX IF NOT EXISTS idx_tracked_companies_owner
+                ON tracked_companies(owner_id)
+            """)
+
+            # ---------- 4. Replace unique constraint on tracked_companies ----------
+            cur.execute("""
+                DO $$
+                BEGIN
+                    IF EXISTS (
+                        SELECT 1 FROM pg_constraint
+                        WHERE conname = 'tracked_companies_company_name_key'
+                    ) THEN
+                        ALTER TABLE tracked_companies
+                            DROP CONSTRAINT tracked_companies_company_name_key;
+                    END IF;
+                END $$;
+            """)
+            cur.execute("""
+                CREATE UNIQUE INDEX IF NOT EXISTS uq_tracked_company_owner
+                ON tracked_companies(LOWER(company_name), owner_id)
+            """)
+
+        conn.commit()
+        print("Migration completed successfully.")
+
+    except Exception:
+        conn.rollback()
+        print("Migration FAILED — rolled back.", file=sys.stderr)
+        raise
+    finally:
+        conn.close()
+
+
+if __name__ == "__main__":
+    print(f"Running owner_id migration against {DATABASE_URL.split('@')[-1]} ...")
+    run_migration()
diff --git a/tests/test_api.py b/tests/test_api.py
index fd16921..e1def71 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -1,12 +1,13 @@
 """Tests for FastAPI web service endpoints."""
 
-from datetime import datetime
-from unittest.mock import Mock
+from datetime import datetime, timezone
+from unittest.mock import Mock, MagicMock, patch
 
 import pytest
 from fastapi.testclient import TestClient
 
 from SPARC.api import app
+from SPARC.auth import create_access_token
 from SPARC.types import BatchAnalysisResult, CompanyAnalysisResult
 
 
@@ -16,6 +17,22 @@ def client():
     return TestClient(app)
 
 
+@pytest.fixture(autouse=True)
+def mock_db():
+    """Mock the database client used by auth endpoints."""
+    db = MagicMock()
+    db.get_user_by_id.return_value = {
+        "id": 1,
+        "email": "user@test.com",
+        "role": "user",
+        "created_at": datetime(2025, 1, 1, tzinfo=timezone.utc),
+    }
+
+    with patch("SPARC.api.get_db_client", return_value=db), \
+         patch("SPARC.auth.get_db_client", return_value=db):
+        yield db
+
+
 @pytest.fixture
 def mock_analyzer(mocker):
     """Mock the global analyzer."""
@@ -24,6 +41,12 @@ def mock_analyzer(mocker):
     return mock
 
 
+def _auth_header(user_id=1, email="user@test.com", role="user"):
+    """Create an Authorization header with a valid access token."""
+    token = create_access_token(user_id, email, role)
+    return {"Authorization": f"Bearer {token}"}
+
+
 class TestHealthEndpoint:
     """Test health check endpoint."""
 
@@ -51,7 +74,7 @@ class TestAnalyzeCompanyEndpoint:
         )
         mock_analyzer._analyze_company_safe.return_value = mock_result
 
-        response = client.get("/analyze/nvidia")
+        response = client.get("/analyze/nvidia", headers=_auth_header())
 
         assert response.status_code == 200
         data = response.json()
@@ -72,7 +95,7 @@ class TestAnalyzeCompanyEndpoint:
         )
         mock_analyzer._analyze_company_safe.return_value = mock_result
 
-        response = client.get("/analyze/unknown")
+        response = client.get("/analyze/unknown", headers=_auth_header())
 
         assert response.status_code == 200
         data = response.json()
@@ -113,6 +136,7 @@ class TestBatchAnalysisEndpoint:
         response = client.post(
             "/analyze/batch",
             json={"companies": ["nvidia", "amd"], "max_workers": 2},
+            headers=_auth_header(),
         )
 
         assert response.status_code == 200
@@ -125,13 +149,14 @@ class TestBatchAnalysisEndpoint:
     def test_batch_analysis_validation(self, client):
         """Test batch analysis request validation."""
         # Empty companies list
-        response = client.post("/analyze/batch", json={"companies": []})
+        response = client.post("/analyze/batch", json={"companies": []}, headers=_auth_header())
         assert response.status_code == 422
 
         # Too many companies
         response = client.post(
             "/analyze/batch",
             json={"companies": [f"company{i}" for i in range(25)]},
+            headers=_auth_header(),
         )
         assert response.status_code == 422
 
@@ -139,6 +164,7 @@ class TestBatchAnalysisEndpoint:
         response = client.post(
             "/analyze/batch",
             json={"companies": ["nvidia"], "max_workers": 10},
+            headers=_auth_header(),
         )
         assert response.status_code == 422
 
@@ -146,11 +172,26 @@ class TestBatchAnalysisEndpoint:
 class TestAsyncBatchEndpoint:
     """Test async batch analysis endpoint."""
 
-    def test_async_batch_creates_job(self, client, mock_analyzer):
-        """Test async endpoint creates a job."""
+    @patch("SPARC.api._get_job_db")
+    def test_async_batch_creates_job(self, mock_get_db, client, mock_analyzer):
+        """Test async endpoint creates a job with owner_id."""
+        job_db = MagicMock()
+        job_db.create_job.return_value = {
+            "job_id": "j1",
+            "status": "pending",
+            "progress": 0,
+            "total_companies": 2,
+            "completed_companies": 0,
+            "result_json": None,
+            "error": None,
+            "owner_id": 1,
+        }
+        mock_get_db.return_value = job_db
+
         response = client.post(
             "/analyze/batch/async",
             json={"companies": ["nvidia", "amd"]},
+            headers=_auth_header(),
         )
 
         assert response.status_code == 200
@@ -159,28 +200,42 @@ class TestAsyncBatchEndpoint:
         assert data["status"] == "pending"
         assert data["total_companies"] == 2
         assert data["progress"] == 0
+        # Verify owner_id was passed
+        job_db.create_job.assert_called_once()
+        assert job_db.create_job.call_args.kwargs.get("owner_id") == 1
 
 
 class TestJobEndpoints:
     """Test job management endpoints."""
 
-    def test_get_job_not_found(self, client):
+    @patch("SPARC.api._get_job_db")
+    def test_get_job_not_found(self, mock_get_db, client):
         """Test getting nonexistent job."""
-        response = client.get("/jobs/nonexistent")
+        job_db = MagicMock()
+        job_db.get_job.return_value = None
+        mock_get_db.return_value = job_db
+
+        response = client.get("/jobs/nonexistent", headers=_auth_header())
         assert response.status_code == 404
 
-    def test_list_jobs(self, client, mocker):
+    @patch("SPARC.api._get_job_db")
+    def test_list_jobs(self, mock_get_db, client):
         """Test listing jobs."""
-        # Clear existing jobs
-        mocker.patch.dict("SPARC.api._jobs", {}, clear=True)
+        job_db = MagicMock()
+        job_db.list_jobs.return_value = []
+        mock_get_db.return_value = job_db
 
-        response = client.get("/jobs")
+        response = client.get("/jobs", headers=_auth_header())
         assert response.status_code == 200
-        assert isinstance(response.json(), list)
 
-    def test_list_jobs_with_filter(self, client, mocker):
+    @patch("SPARC.api._get_job_db")
+    def test_list_jobs_with_filter(self, mock_get_db, client):
         """Test listing jobs with status filter."""
-        response = client.get("/jobs?status=completed")
+        job_db = MagicMock()
+        job_db.list_jobs.return_value = []
+        mock_get_db.return_value = job_db
+
+        response = client.get("/jobs?status=completed", headers=_auth_header())
         assert response.status_code == 200
 
 
@@ -189,7 +244,7 @@ class TestModelValidation:
 
     def test_analyze_rejects_unsupported_model(self, client, mock_analyzer):
         """GET /analyze/{company} with unsupported model returns 400."""
-        response = client.get("/analyze/nvidia?model=fake/nonexistent-model")
+        response = client.get("/analyze/nvidia?model=fake/nonexistent-model", headers=_auth_header())
         assert response.status_code == 400
         assert "Unsupported model" in response.json()["detail"]
 
@@ -205,7 +260,7 @@ class TestModelValidation:
         )
         mock_analyzer._analyze_company_safe.return_value = mock_result
 
-        response = client.get("/analyze/nvidia?model=anthropic/claude-3.5-sonnet")
+        response = client.get("/analyze/nvidia?model=anthropic/claude-3.5-sonnet", headers=_auth_header())
         assert response.status_code == 200
 
     def test_batch_rejects_unsupported_model(self, client, mock_analyzer):
@@ -213,6 +268,7 @@ class TestModelValidation:
         response = client.post(
             "/analyze/batch",
             json={"companies": ["nvidia"], "model": "fake/nonexistent-model"},
+            headers=_auth_header(),
         )
         assert response.status_code == 400
         assert "Unsupported model" in response.json()["detail"]
diff --git a/tests/test_export.py b/tests/test_export.py
index d0c856f..321e443 100644
--- a/tests/test_export.py
+++ b/tests/test_export.py
@@ -5,6 +5,7 @@ Covers issue #1655:
 - GET /export/{company_name}/pdf (PDF export)
 
 All tests mock the database layer and use JWT auth fixtures from test_auth patterns.
+Export queries are now scoped to the current user's owner_id.
 """
 
 from datetime import datetime, timezone
diff --git a/tests/test_multi_tenant.py b/tests/test_multi_tenant.py
new file mode 100644
index 0000000..7ce758d
--- /dev/null
+++ b/tests/test_multi_tenant.py
@@ -0,0 +1,281 @@
+"""Cross-tenant isolation tests for multi-tenant support.
+
+Verifies that:
+- User A cannot read, update, or delete User B's analyses, tracked companies, or jobs
+- Admin users can access all data via admin endpoints
+- owner_id is correctly set on new resources
+"""
+
+from datetime import datetime, timezone
+from unittest.mock import MagicMock, Mock, patch
+
+import pytest
+from fastapi.testclient import TestClient
+
+from SPARC.api import app
+from SPARC.auth import create_access_token
+
+
+@pytest.fixture
+def client():
+    """Create test client."""
+    return TestClient(app)
+
+
+def _make_user(user_id, email, role="user"):
+    return {
+        "id": user_id,
+        "email": email,
+        "role": role,
+        "created_at": datetime(2025, 1, 1, tzinfo=timezone.utc),
+    }
+
+
+USER_A = _make_user(10, "alice@test.com")
+USER_B = _make_user(20, "bob@test.com")
+ADMIN = _make_user(1, "admin@test.com", role="admin")
+
+
+def _header_for(user):
+    token = create_access_token(user["id"], user["email"], user["role"])
+    return {"Authorization": f"Bearer {token}"}
+
+
+@pytest.fixture(autouse=True)
+def mock_db():
+    """Mock DB returning the correct user based on user_id."""
+    db = MagicMock()
+
+    def _get_user_by_id(uid):
+        for u in [USER_A, USER_B, ADMIN]:
+            if u["id"] == uid:
+                return u
+        return None
+
+    db.get_user_by_id.side_effect = _get_user_by_id
+
+    with patch("SPARC.api.get_db_client", return_value=db), \
+         patch("SPARC.auth.get_db_client", return_value=db):
+        yield db
+
+
+# ==================== Tracked Companies Isolation ====================
+
+
+class TestTrackedCompanyIsolation:
+    """User A's tracked companies are invisible to User B."""
+
+    def test_user_a_list_scoped_to_own(self, client, mock_db):
+        """GET /tracked returns only User A's companies."""
+        mock_db.list_tracked_companies.return_value = [
+            {"company_name": "AliceCo", "owner_id": USER_A["id"]},
+        ]
+
+        response = client.get("/tracked", headers=_header_for(USER_A))
+        assert response.status_code == 200
+        mock_db.list_tracked_companies.assert_called_with(owner_id=USER_A["id"])
+
+    def test_user_b_list_scoped_to_own(self, client, mock_db):
+        """GET /tracked returns only User B's companies."""
+        mock_db.list_tracked_companies.return_value = []
+
+        response = client.get("/tracked", headers=_header_for(USER_B))
+        assert response.status_code == 200
+        mock_db.list_tracked_companies.assert_called_with(owner_id=USER_B["id"])
+
+    def test_user_a_add_sets_owner(self, client, mock_db):
+        """POST /tracked sets owner_id to User A."""
+        mock_db.add_tracked_company.return_value = {"company_name": "NewCo", "owner_id": 10}
+
+        response = client.post("/tracked", json={"company_name": "NewCo"}, headers=_header_for(USER_A))
+        assert response.status_code == 200
+        mock_db.add_tracked_company.assert_called_with("NewCo", owner_id=USER_A["id"])
+
+    def test_user_b_cannot_remove_user_a_company(self, client, mock_db):
+        """DELETE /tracked/{name} filters by owner, so B can't remove A's company."""
+        mock_db.remove_tracked_company.return_value = False  # not found for B
+
+        response = client.delete("/tracked/AliceCo", headers=_header_for(USER_B))
+        assert response.status_code == 404
+        mock_db.remove_tracked_company.assert_called_with("AliceCo", owner_id=USER_B["id"])
+
+
+# ==================== Job Isolation ====================
+
+
+class TestJobIsolation:
+    """User A's jobs are invisible to User B."""
+
+    def test_user_a_get_own_job(self, client, mock_db):
+        """GET /jobs/{id} scoped to User A returns the job."""
+        mock_db.get_job.return_value = None  # mock via _get_job_db
+
+        with patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.get_job.return_value = {
+                "job_id": "j1",
+                "status": "completed",
+                "progress": 100,
+                "total_companies": 1,
+                "completed_companies": 1,
+                "result_json": None,
+                "error": None,
+                "owner_id": USER_A["id"],
+            }
+            mock_get_db.return_value = job_db
+
+            response = client.get("/jobs/j1", headers=_header_for(USER_A))
+            assert response.status_code == 200
+            job_db.get_job.assert_called_with("j1", owner_id=USER_A["id"])
+
+    def test_user_b_cannot_see_user_a_job(self, client, mock_db):
+        """GET /jobs/{id} returns 404 when User B tries to access User A's job."""
+        with patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.get_job.return_value = None  # not found for B's owner_id
+            mock_get_db.return_value = job_db
+
+            response = client.get("/jobs/j1", headers=_header_for(USER_B))
+            assert response.status_code == 404
+            job_db.get_job.assert_called_with("j1", owner_id=USER_B["id"])
+
+    def test_list_jobs_scoped_to_user(self, client, mock_db):
+        """GET /jobs filters by owner_id."""
+        with patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.list_jobs.return_value = []
+            mock_get_db.return_value = job_db
+
+            response = client.get("/jobs", headers=_header_for(USER_A))
+            assert response.status_code == 200
+            call_kwargs = job_db.list_jobs.call_args
+            assert call_kwargs.kwargs.get("owner_id") == USER_A["id"]
+
+    def test_async_job_created_with_owner(self, client, mock_db):
+        """POST /analyze/batch/async creates job with current user's owner_id."""
+        mock_analyzer = MagicMock()
+        with patch("SPARC.api._analyzer", mock_analyzer), \
+             patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.create_job.return_value = {
+                "job_id": "j2",
+                "status": "pending",
+                "progress": 0,
+                "total_companies": 1,
+                "completed_companies": 0,
+                "result_json": None,
+                "error": None,
+                "owner_id": USER_A["id"],
+            }
+            mock_get_db.return_value = job_db
+
+            response = client.post(
+                "/analyze/batch/async",
+                json={"companies": ["nvidia"]},
+                headers=_header_for(USER_A),
+            )
+            assert response.status_code == 200
+            create_kwargs = job_db.create_job.call_args
+            assert create_kwargs.kwargs.get("owner_id") == USER_A["id"]
+
+
+# ==================== Analysis Listing Isolation ====================
+
+
+class TestAnalysisListIsolation:
+    """GET /analyze/batch scoped to current user."""
+
+    def test_list_analyses_scoped_to_user(self, client, mock_db):
+        """GET /analyze/batch passes owner_id to db.list_analyses."""
+        with patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.list_analyses.return_value = []
+            mock_get_db.return_value = job_db
+
+            response = client.get("/analyze/batch", headers=_header_for(USER_A))
+            assert response.status_code == 200
+            call_kwargs = job_db.list_analyses.call_args
+            assert call_kwargs.kwargs.get("owner_id") == USER_A["id"]
+
+
+# ==================== Admin Cross-Tenant Access ====================
+
+
+class TestAdminCrossTenantAccess:
+    """Admin endpoints return data from all tenants (no owner_id filter)."""
+
+    def test_admin_list_tracked_all_tenants(self, client, mock_db):
+        """GET /admin/tracked returns all companies (no owner_id filter)."""
+        mock_db.list_tracked_companies.return_value = [
+            {"company_name": "AliceCo", "owner_id": 10},
+            {"company_name": "BobCo", "owner_id": 20},
+        ]
+
+        response = client.get("/admin/tracked", headers=_header_for(ADMIN))
+        assert response.status_code == 200
+        # Should be called without owner_id filter
+        mock_db.list_tracked_companies.assert_called_with()
+
+    def test_admin_list_analyses_all_tenants(self, client, mock_db):
+        """GET /admin/analyses returns all analyses (no owner_id filter)."""
+        with patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.list_analyses.return_value = []
+            mock_get_db.return_value = job_db
+
+            response = client.get("/admin/analyses", headers=_header_for(ADMIN))
+            assert response.status_code == 200
+            call_kwargs = job_db.list_analyses.call_args
+            # No owner_id should be passed
+            assert "owner_id" not in call_kwargs.kwargs or call_kwargs.kwargs["owner_id"] is None
+
+    def test_admin_list_jobs_all_tenants(self, client, mock_db):
+        """GET /admin/jobs returns all jobs (no owner_id filter)."""
+        with patch("SPARC.api._get_job_db") as mock_get_db:
+            job_db = MagicMock()
+            job_db.list_jobs.return_value = []
+            mock_get_db.return_value = job_db
+
+            response = client.get("/admin/jobs", headers=_header_for(ADMIN))
+            assert response.status_code == 200
+            call_kwargs = job_db.list_jobs.call_args
+            assert "owner_id" not in call_kwargs.kwargs or call_kwargs.kwargs["owner_id"] is None
+
+    def test_admin_remove_tracked_any_owner(self, client, mock_db):
+        """DELETE /admin/tracked/{name} removes without owner filter."""
+        mock_db.remove_tracked_company.return_value = True
+
+        response = client.delete("/admin/tracked/SomeCo", headers=_header_for(ADMIN))
+        assert response.status_code == 200
+        # Called without owner_id
+        mock_db.remove_tracked_company.assert_called_with("SomeCo")
+
+    def test_regular_user_cannot_access_admin_analyses(self, client, mock_db):
+        """Regular user gets 403 on /admin/analyses."""
+        response = client.get("/admin/analyses", headers=_header_for(USER_A))
+        assert response.status_code == 403
+
+    def test_regular_user_cannot_access_admin_jobs(self, client, mock_db):
+        """Regular user gets 403 on /admin/jobs."""
+        response = client.get("/admin/jobs", headers=_header_for(USER_A))
+        assert response.status_code == 403
+
+
+# ==================== Analytics Isolation ====================
+
+
+class TestAnalyticsIsolation:
+    """GET /analytics scoped to current user."""
+
+    def test_analytics_scoped_to_user(self, client, mock_db):
+        """GET /analytics passes owner_id to db.get_analytics."""
+        mock_db.get_analytics.return_value = {
+            "total_messages": 5,
+            "by_company": [],
+            "by_type": [],
+            "period_days": 30,
+        }
+
+        response = client.get("/analytics", headers=_header_for(USER_A))
+        assert response.status_code == 200
+        mock_db.get_analytics.assert_called_with(days=30, owner_id=USER_A["id"])
diff --git a/tests/test_pagination.py b/tests/test_pagination.py
index 01bc5b3..0f3cc2d 100644
--- a/tests/test_pagination.py
+++ b/tests/test_pagination.py
@@ -1,12 +1,13 @@
 """Tests for cursor-based pagination on /analyze/batch GET and /jobs endpoints."""
 
-from datetime import datetime, timedelta
-from unittest.mock import Mock, patch
+from datetime import datetime, timedelta, timezone
+from unittest.mock import Mock, MagicMock, patch
 
 import pytest
 from fastapi.testclient import TestClient
 
 from SPARC.api import app
+from SPARC.auth import create_access_token
 
 
 @pytest.fixture
@@ -15,6 +16,27 @@ def client():
     return TestClient(app)
 
 
+@pytest.fixture(autouse=True)
+def mock_db():
+    """Mock the database client used by auth endpoints."""
+    db = MagicMock()
+    db.get_user_by_id.return_value = {
+        "id": 1,
+        "email": "user@test.com",
+        "role": "user",
+        "created_at": datetime(2025, 1, 1, tzinfo=timezone.utc),
+    }
+
+    with patch("SPARC.api.get_db_client", return_value=db), \
+         patch("SPARC.auth.get_db_client", return_value=db):
+        yield db
+
+
+def _auth_header():
+    token = create_access_token(1, "user@test.com", "user")
+    return {"Authorization": f"Bearer {token}"}
+
+
 def _make_analysis_row(id_: int, minutes_ago: int = 0, company: str = "nvidia"):
     """Create a fake analysis row dict."""
     ts = datetime.now() - timedelta(minutes=minutes_ago)
@@ -56,7 +78,7 @@ class TestAnalyzeBatchGetPagination:
         ]
         mock_get_db.return_value = db
 
-        response = client.get("/analyze/batch?limit=10")
+        response = client.get("/analyze/batch?limit=10", headers=_auth_header())
         assert response.status_code == 200
         data = response.json()
         assert len(data["items"]) == 2
@@ -71,7 +93,7 @@ class TestAnalyzeBatchGetPagination:
         db.list_analyses.return_value = rows
         mock_get_db.return_value = db
 
-        response = client.get("/analyze/batch?limit=3")
+        response = client.get("/analyze/batch?limit=3", headers=_auth_header())
         assert response.status_code == 200
         data = response.json()
         assert len(data["items"]) == 3
@@ -84,7 +106,7 @@ class TestAnalyzeBatchGetPagination:
         db.list_analyses.return_value = []
         mock_get_db.return_value = db
 
-        client.get("/analyze/batch?cursor=2025-01-01T00:00:00|42")
+        client.get("/analyze/batch?cursor=2025-01-01T00:00:00|42", headers=_auth_header())
         db.list_analyses.assert_called_once()
         call_kwargs = db.list_analyses.call_args
         assert call_kwargs.kwargs.get("cursor") == "2025-01-01T00:00:00|42" or \
@@ -97,19 +119,19 @@ class TestAnalyzeBatchGetPagination:
         db.list_analyses.return_value = []
         mock_get_db.return_value = db
 
-        client.get("/analyze/batch")
+        client.get("/analyze/batch", headers=_auth_header())
         call_kwargs = db.list_analyses.call_args
         # The endpoint requests limit+1 from DB, so 51
         assert 51 in call_kwargs.args or call_kwargs.kwargs.get("limit") == 51
 
     def test_limit_over_200_rejected(self, client):
         """Limit > 200 should be rejected with 422."""
-        response = client.get("/analyze/batch?limit=201")
+        response = client.get("/analyze/batch?limit=201", headers=_auth_header())
         assert response.status_code == 422
 
     def test_limit_zero_rejected(self, client):
         """Limit < 1 should be rejected with 422."""
-        response = client.get("/analyze/batch?limit=0")
+        response = client.get("/analyze/batch?limit=0", headers=_auth_header())
         assert response.status_code == 422
 
     @patch("SPARC.api._get_job_db")
@@ -119,7 +141,7 @@ class TestAnalyzeBatchGetPagination:
         db.list_analyses.return_value = []
         mock_get_db.return_value = db
 
-        client.get("/analyze/batch?company_name=intel")
+        client.get("/analyze/batch?company_name=intel", headers=_auth_header())
         call_kwargs = db.list_analyses.call_args
         assert call_kwargs.kwargs.get("company_name") == "intel" or \
             "intel" in (call_kwargs.args if call_kwargs.args else [])
@@ -131,7 +153,7 @@ class TestAnalyzeBatchGetPagination:
         db.list_analyses.return_value = []
         mock_get_db.return_value = db
 
-        response = client.get("/analyze/batch")
+        response = client.get("/analyze/batch", headers=_auth_header())
         assert response.status_code == 200
         data = response.json()
         assert data["items"] == []
@@ -148,14 +170,14 @@ class TestJobsPaginationDefaults:
         db.list_jobs.return_value = []
         mock_get_db.return_value = db
 
-        client.get("/jobs")
+        client.get("/jobs", headers=_auth_header())
         call_kwargs = db.list_jobs.call_args
         # Endpoint requests limit+1 from DB, so 51
         assert 51 in call_kwargs.args or call_kwargs.kwargs.get("limit") == 51
 
     def test_limit_over_200_rejected(self, client):
         """Limit > 200 should be rejected with 422."""
-        response = client.get("/jobs?limit=201")
+        response = client.get("/jobs?limit=201", headers=_auth_header())
         assert response.status_code == 422
 
     @patch("SPARC.api._get_job_db")
@@ -165,5 +187,5 @@ class TestJobsPaginationDefaults:
         db.list_jobs.return_value = []
         mock_get_db.return_value = db
 
-        response = client.get("/jobs?limit=200")
+        response = client.get("/jobs?limit=200", headers=_auth_header())
         assert response.status_code == 200
diff --git a/tests/test_tracked_companies.py b/tests/test_tracked_companies.py
index df25134..4aec720 100644
--- a/tests/test_tracked_companies.py
+++ b/tests/test_tracked_companies.py
@@ -1,17 +1,18 @@
-"""Tests for tracked company admin endpoints and scheduler integration.
+"""Tests for tracked company endpoints and scheduler integration.
 
-Covers issue #1656:
-- GET /admin/tracked (list tracked companies)
-- POST /admin/tracked (add a tracked company)
-- DELETE /admin/tracked/{company_name} (remove a tracked company)
+Covers:
+- GET /tracked (user-scoped list)
+- POST /tracked (user-scoped add)
+- DELETE /tracked/{company_name} (user-scoped remove)
+- GET /admin/tracked (admin: all companies)
+- POST /admin/tracked (admin: add)
+- DELETE /admin/tracked/{company_name} (admin: remove any)
 - GET /admin/alerts (list alerts)
 - scheduler.run_scheduled_analysis() integration
-
-All tests mock the database layer and use JWT auth fixtures.
 """
 
 from datetime import datetime, timezone
-from unittest.mock import MagicMock, patch, call
+from unittest.mock import MagicMock, patch
 
 import pytest
 from fastapi.testclient import TestClient
@@ -125,7 +126,7 @@ class TestAddTrackedCompany:
         assert response.status_code == 200
         data = response.json()
         assert data["company_name"] == "Intel"
-        mock_db.add_tracked_company.assert_called_once_with("Intel")
+        mock_db.add_tracked_company.assert_called_once_with("Intel", owner_id=1)
 
     def test_add_duplicate_returns_409(self, client, mock_db):
         """Adding an already-tracked company returns 409."""
@@ -141,7 +142,7 @@ class TestAddTrackedCompany:
         assert "already tracked" in response.json()["detail"].lower()
 
     def test_add_tracked_requires_admin(self, client, mock_db):
-        """Regular user cannot add tracked companies."""
+        """Regular user cannot add tracked companies via admin endpoint."""
         mock_db.get_user_by_id.return_value = {
             "id": 2,
             "email": "user@test.com",
@@ -215,6 +216,66 @@ class TestRemoveTrackedCompany:
         assert response.status_code == 403
 
 
+# ---------- User-scoped tracked companies ----------
+
+class TestUserScopedTrackedCompanies:
+    """Tests for /tracked user-scoped endpoints."""
+
+    def test_user_list_tracked(self, client, mock_db):
+        """Regular user can list their own tracked companies."""
+        mock_db.get_user_by_id.return_value = {
+            "id": 2,
+            "email": "user@test.com",
+            "role": "user",
+            "created_at": datetime(2025, 1, 1, tzinfo=timezone.utc),
+        }
+        mock_db.list_tracked_companies.return_value = [
+            {"company_name": "AMD", "owner_id": 2},
+        ]
+
+        response = client.get("/tracked", headers=_user_header())
+
+        assert response.status_code == 200
+        mock_db.list_tracked_companies.assert_called_with(owner_id=2)
+
+    def test_user_add_tracked(self, client, mock_db):
+        """Regular user can add a company to their own tracked list."""
+        mock_db.get_user_by_id.return_value = {
+            "id": 2,
+            "email": "user@test.com",
+            "role": "user",
+            "created_at": datetime(2025, 1, 1, tzinfo=timezone.utc),
+        }
+        mock_db.add_tracked_company.return_value = {
+            "company_name": "Intel",
+            "owner_id": 2,
+        }
+
+        response = client.post(
+            "/tracked",
+            json={"company_name": "Intel"},
+            headers=_user_header(),
+        )
+
+        assert response.status_code == 200
+        mock_db.add_tracked_company.assert_called_once_with("Intel", owner_id=2)
+
+    def test_user_remove_tracked(self, client, mock_db):
+        """Regular user can remove a company from their own tracked list."""
+        mock_db.get_user_by_id.return_value = {
+            "id": 2,
+            "email": "user@test.com",
+            "role": "user",
+            "created_at": datetime(2025, 1, 1, tzinfo=timezone.utc),
+        }
+        mock_db.remove_tracked_company.return_value = True
+
+        response = client.delete("/tracked/Intel", headers=_user_header())
+
+        assert response.status_code == 200
+        mock_db.remove_tracked_company.assert_called_once_with("Intel", owner_id=2)
+
+
 # ---------- GET /admin/alerts ----------
 
 class TestListAlerts: