diff --git a/app/models.py b/app/models.py
index a20f49ecdc88904ee66da70ab188b40ce2d1bcad..1c173720d8df51fee070c4bf6ba9a73c6f9558e0 100644
--- a/app/models.py
+++ b/app/models.py
@@ -1,3 +1,4 @@
+from datetime import datetime, timezone
 from app import db
 
 
@@ -33,6 +34,7 @@ class Job(db.Model):
     quantity = db.Column(db.Integer, nullable=False)
     threshold_percent = db.Column(db.Float, nullable=False, default=20.0)
     status = db.Column(db.String(20), nullable=False, default="Draft")
+    barcode = db.Column(db.String(30), unique=True)
 
     steps = db.relationship(
         "JobStep",
@@ -95,10 +97,97 @@ class StepPart(db.Model):
     step = db.relationship("JobStep", back_populates="parts")
     part = db.relationship("Part", back_populates="step_usages")
 
-    __table_args__ = (
+    _table_args__ = (
         db.UniqueConstraint(
             "step_id",
             "part_id",
             name="uq_step_part",
         ),
+    )
+class StationInventory(db.Model):
+    __tablename__ = "station_inventory"
+
+    id = db.Column(db.Integer, primary_key=True)
+    station_id = db.Column(
+        db.String(5),
+        db.ForeignKey("stations.id"),
+        nullable=False,
+    )
+    part_id = db.Column(
+        db.Integer,
+        db.ForeignKey("parts.id"),
+        nullable=False,
+    )
+    quantity = db.Column(db.Integer, nullable=False, default=0)
+
+    station = db.relationship("Station")
+    part = db.relationship("Part")
+
+    __table_args__ = (
+        db.UniqueConstraint(
+            "station_id",
+            "part_id",
+            name="uq_station_part_inventory",
+        ),
+    )
+
+
+class TransferRequest(db.Model):
+    __tablename__ = "transfer_requests"
+
+    id = db.Column(db.Integer, primary_key=True)
+    job_id = db.Column(
+        db.Integer,
+        db.ForeignKey("jobs.id"),
+        nullable=False,
+    )
+    station_id = db.Column(
+        db.String(5),
+        db.ForeignKey("stations.id"),
+        nullable=False,
+    )
+    part_id = db.Column(
+        db.Integer,
+        db.ForeignKey("parts.id"),
+        nullable=False,
+    )
+
+    requested_quantity = db.Column(db.Integer, nullable=False)
+    transferred_quantity = db.Column(db.Integer, nullable=False, default=0)
+    status = db.Column(db.String(30), nullable=False, default="Pending")
+
+    created_at = db.Column(
+        db.DateTime,
+        nullable=False,
+        default=lambda: datetime.now(timezone.utc),
+    )
+    completed_at = db.Column(db.DateTime)
+
+    job = db.relationship("Job")
+    station = db.relationship("Station")
+    part = db.relationship("Part")
+
+
+class ProductUnit(db.Model):
+    __tablename__ = "product_units"
+
+    id = db.Column(db.Integer, primary_key=True)
+    job_id = db.Column(
+        db.Integer,
+        db.ForeignKey("jobs.id"),
+        nullable=False,
+    )
+    unit_number = db.Column(db.Integer, nullable=False)
+
+
+    status = db.Column(db.String(20), nullable=False, default="Pending")
+
+    job = db.relationship("Job")
+
+    __table_args__ = (
+        db.UniqueConstraint(
+            "job_id",
+            "unit_number",
+            name="uq_job_unit_number",
+        ),
     )
\ No newline at end of file
diff --git a/app/routes.py b/app/routes.py
index b8be6dcdab801a1d430af4a3a59edd7893b34723..6769c7ac099f1f7488b16639836e8bb78f918a4c 100644
--- a/app/routes.py
+++ b/app/routes.py
@@ -1,7 +1,21 @@
 from flask import Blueprint, abort, redirect, render_template, request, url_for
 
 from app import db
-from app.models import Job, JobStep, Part, Station, StepPart
+from app.models import (
+    Job,
+    JobStep,
+    Part,
+    ProductUnit,
+    Station,
+    StationInventory,
+    StepPart,
+    TransferRequest,
+)
+from app.services import (
+    activate_job,
+    fulfill_transfer_request,
+    set_station_inventory,
+)
 
 
 bp = Blueprint("main", __name__)
@@ -18,8 +32,16 @@ def admin_jobs():
         name = request.form["name"].strip()
         quantity = int(request.form["quantity"])
 
-        threshold_value = request.form.get("threshold_percent", "").strip()
-        threshold_percent = float(threshold_value) if threshold_value else 20.0
+        threshold_value = request.form.get(
+            "threshold_percent",
+            "",
+        ).strip()
+
+        threshold_percent = (
+            float(threshold_value)
+            if threshold_value
+            else 20.0
+        )
 
         job = Job(
             name=name,
@@ -31,10 +53,16 @@ def admin_jobs():
         db.session.add(job)
         db.session.commit()
 
-        return redirect(url_for("main.job_detail", job_id=job.id))
+        return redirect(
+            url_for("main.job_detail", job_id=job.id)
+        )
 
     jobs = Job.query.order_by(Job.id.desc()).all()
-    return render_template("admin_jobs.html", jobs=jobs)
+
+    return render_template(
+        "admin_jobs.html",
+        jobs=jobs,
+    )
 
 
 @bp.route("/admin/jobs/<int:job_id>", methods=["GET", "POST"])
@@ -68,7 +96,10 @@ def job_detail(job_id):
             step_number=next_step_number,
             instruction=request.form["instruction"].strip(),
             station=station,
-            photo_url=request.form.get("photo_url", "").strip() or None,
+            photo_url=request.form.get(
+                "photo_url",
+                "",
+            ).strip() or None,
         )
 
         db.session.add(step)
@@ -82,10 +113,100 @@ def job_detail(job_id):
         db.session.add(step_part)
         db.session.commit()
 
-        return redirect(url_for("main.job_detail", job_id=job.id))
+        return redirect(
+            url_for("main.job_detail", job_id=job.id)
+        )
+
+    product_units = ProductUnit.query.filter_by(
+        job_id=job.id
+    ).order_by(ProductUnit.unit_number).all()
+
+    transfer_requests = TransferRequest.query.filter_by(
+        job_id=job.id
+    ).order_by(TransferRequest.id.desc()).all()
 
     return render_template(
         "job_detail.html",
         job=job,
         stations=stations,
+        product_units=product_units,
+        transfer_requests=transfer_requests,
+    )
+
+
+@bp.route(
+    "/admin/jobs/<int:job_id>/activate",
+    methods=["POST"],
+)
+def activate_job_route(job_id):
+    job = db.get_or_404(Job, job_id)
+
+    activate_job(job)
+
+    return redirect(
+        url_for("main.job_detail", job_id=job.id)
+    )
+
+
+@bp.route("/admin/inventory", methods=["GET", "POST"])
+def admin_inventory():
+    if request.method == "POST":
+        station_id = request.form["station_id"]
+        part_id = int(request.form["part_id"])
+        quantity = int(request.form["quantity"])
+
+        set_station_inventory(
+            station_id,
+            part_id,
+            quantity,
+        )
+
+        return redirect(
+            url_for("main.admin_inventory")
+        )
+
+    stations = Station.query.order_by(Station.id).all()
+    parts = Part.query.order_by(Part.name).all()
+
+    inventory_rows = StationInventory.query.order_by(
+        StationInventory.station_id,
+        StationInventory.part_id,
+    ).all()
+
+    return render_template(
+        "admin_inventory.html",
+        stations=stations,
+        parts=parts,
+        inventory_rows=inventory_rows,
+    )
+
+
+@bp.route("/warehouse/requests")
+def warehouse_requests():
+    transfer_requests = TransferRequest.query.order_by(
+        TransferRequest.id.desc()
+    ).all()
+
+    return render_template(
+        "transfer_requests.html",
+        transfer_requests=transfer_requests,
+    )
+
+
+@bp.route(
+    "/warehouse/requests/<int:request_id>/fulfill",
+    methods=["POST"],
+)
+def fulfill_request_route(request_id):
+    transferred_quantity = int(
+        request.form["transferred_quantity"]
+    )
+
+    fulfill_transfer_request(
+        request_id,
+        transferred_quantity,
+    )
+
+    return redirect(
+        url_for("main.warehouse_requests")
     )
\ No newline at end of file
diff --git a/app/services.py b/app/services.py
new file mode 100644
index 0000000000000000000000000000000000000000..43e27732a4d5154ffe6d9b44bbe71d74b68da50a
--- /dev/null
+++ b/app/services.py
@@ -0,0 +1,161 @@
+from datetime import datetime, timezone
+import uuid
+
+from app import db
+from app.models import (
+    Job,
+    ProductUnit,
+    StationInventory,
+    TransferRequest,
+)
+
+
+def calculate_requirements(job):
+    requirements = {}
+
+    for step in job.steps:
+        for usage in step.parts:
+            key = (step.station_id, usage.part_id)
+
+            total_required = usage.quantity * job.quantity
+
+            requirements[key] = (
+                requirements.get(key, 0) + total_required
+            )
+
+    return requirements
+
+
+def get_or_create_station_inventory(station_id, part_id):
+    inventory = StationInventory.query.filter_by(
+        station_id=station_id,
+        part_id=part_id,
+    ).first()
+
+    if inventory is None:
+        inventory = StationInventory(
+            station_id=station_id,
+            part_id=part_id,
+            quantity=0,
+        )
+        db.session.add(inventory)
+
+    return inventory
+
+
+def set_station_inventory(station_id, part_id, quantity):
+    inventory = get_or_create_station_inventory(
+        station_id,
+        part_id,
+    )
+
+    inventory.quantity = quantity
+    db.session.commit()
+
+    return inventory
+
+
+def activate_job(job):
+    requirements = calculate_requirements(job)
+
+    stock_missing = False
+
+    for (station_id, part_id), required_quantity in requirements.items():
+        inventory = get_or_create_station_inventory(
+            station_id,
+            part_id,
+        )
+
+        threshold_quantity = (
+            required_quantity * job.threshold_percent / 100
+        )
+
+        if inventory.quantity < threshold_quantity:
+            stock_missing = True
+
+            existing_request = TransferRequest.query.filter(
+                TransferRequest.job_id == job.id,
+                TransferRequest.station_id == station_id,
+                TransferRequest.part_id == part_id,
+                TransferRequest.status.in_(
+                    ["Pending", "Partially Fulfilled"]
+                ),
+            ).first()
+
+            if existing_request is None:
+                requested_quantity = (
+                    required_quantity - inventory.quantity
+                )
+
+                if requested_quantity > 0:
+                    db.session.add(
+                        TransferRequest(
+                            job_id=job.id,
+                            station_id=station_id,
+                            part_id=part_id,
+                            requested_quantity=requested_quantity,
+                            status="Pending",
+                        )
+                    )
+    if stock_missing:
+        db.session.commit()
+        return False
+
+    if job.barcode is None:
+        job.barcode = f"MES-{uuid.uuid4().hex[:12].upper()}"
+
+    job.status = "Active"
+
+    existing_unit_numbers = {
+        unit.unit_number
+        for unit in ProductUnit.query.filter_by(job_id=job.id).all()
+    }
+
+    for unit_number in range(1, job.quantity + 1):
+        if unit_number not in existing_unit_numbers:
+            db.session.add(
+                ProductUnit(
+                    job_id=job.id,
+                    unit_number=unit_number,
+                )
+            )
+
+    db.session.commit()
+    return True
+
+
+def fulfill_transfer_request(request_id, transferred_quantity):
+    transfer_request = db.session.get(
+        TransferRequest,
+        request_id,
+    )
+
+    if transfer_request is None:
+        raise ValueError("Transfer request not found")
+
+    if transferred_quantity <= 0:
+        raise ValueError("Transferred quantity must be greater than zero")
+
+    inventory = get_or_create_station_inventory(
+        transfer_request.station_id,
+        transfer_request.part_id,
+    )
+
+    inventory.quantity += transferred_quantity
+    transfer_request.transferred_quantity += transferred_quantity
+
+    if (
+        transfer_request.transferred_quantity
+        >= transfer_request.requested_quantity
+    ):
+        transfer_request.status = "Fulfilled"
+        transfer_request.completed_at = datetime.now(timezone.utc)
+    else:
+        transfer_request.status = "Partially Fulfilled"
+
+    if transfer_request.job.status == "Draft":
+        activate_job(transfer_request.job)
+    else:
+        db.session.commit()
+
+    return transfer_request
\ No newline at end of file
diff --git a/app/templates/admin_inventory.html b/app/templates/admin_inventory.html
new file mode 100644
index 0000000000000000000000000000000000000000..7c1e63cc7b100eae9d7546a7b429340419f577c5
--- /dev/null
+++ b/app/templates/admin_inventory.html
@@ -0,0 +1,84 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>MES - Station Inventory</title>
+</head>
+<body>
+    <p>
+        <a href="{{ url_for('main.admin_jobs') }}">Production Jobs</a>
+        |
+        <a href="{{ url_for('main.warehouse_requests') }}">
+            Warehouse Requests
+        </a>
+    </p>
+
+    <h1>Station Inventory</h1>
+
+    <h2>Update Station Inventory</h2>
+
+    {% if parts %}
+        <form method="post">
+            <p>
+                <label>Station</label><br>
+                <select name="station_id" required>
+                    {% for station in stations %}
+                        <option value="{{ station.id }}">
+                            {{ station.id }} - {{ station.name }}
+                        </option>
+                    {% endfor %}
+                </select>
+            </p>
+
+            <p>
+                <label>Part</label><br>
+                <select name="part_id" required>
+                    {% for part in parts %}
+                        <option value="{{ part.id }}">
+                            {{ part.name }}
+                        </option>
+                    {% endfor %}
+                </select>
+            </p>
+
+            <p>
+                <label>Quantity</label><br>
+                <input
+                    type="number"
+                    name="quantity"
+                    min="0"
+                    required
+                >
+            </p>
+
+            <button type="submit">Update Inventory</button>
+        </form>
+    {% else %}
+        <p>
+            No parts exist yet. Create a production job and add a step first.
+        </p>
+    {% endif %}
+
+    <h2>Current Station Inventory</h2>
+
+    {% if inventory_rows %}
+        <table border="1" cellpadding="8">
+            <tr>
+                <th>Station</th>
+                <th>Part</th>
+                <th>Quantity</th>
+            </tr>
+
+            {% for inventory in inventory_rows %}
+                <tr>
+                    <td>{{ inventory.station.name }}</td>
+                    <td>{{ inventory.part.name }}</td>
+                    <td>{{ inventory.quantity }}</td>
+                </tr>
+            {% endfor %}
+        </table>
+    {% else %}
+        <p>No station inventory entered yet.</p>
+    {% endif %}
+</body>
+</html>
\ No newline at end of file
diff --git a/app/templates/admin_jobs.html b/app/templates/admin_jobs.html
index 02a4421df170b19760d97d2baecc355bf9e62507..6ea3800ece44dd606fee9ed2ada02f5c7765d737 100644
--- a/app/templates/admin_jobs.html
+++ b/app/templates/admin_jobs.html
@@ -5,6 +5,14 @@
     <title>MES - Production Jobs</title>
 </head>
 <body>
+    <p>
+        <a href="{{ url_for('main.admin_jobs') }}">Production Jobs</a>
+        |
+        <a href="{{ url_for('main.admin_inventory') }}">Station Inventory</a>
+        |
+        <a href="{{ url_for('main.warehouse_requests') }}">Warehouse Requests</a>
+    </p>
+
     <h1>Production Jobs</h1>
 
     <h2>Create Production Job</h2>
diff --git a/app/templates/job_detail.html b/app/templates/job_detail.html
index fd25713228055c1b7d08cf0f4452ae6459e2f3f4..9440225fe5bf83b52dfad48e7a80b1a55f897c44 100644
--- a/app/templates/job_detail.html
+++ b/app/templates/job_detail.html
@@ -6,7 +6,11 @@
 </head>
 <body>
     <p>
-        <a href="{{ url_for('main.admin_jobs') }}">Back to Jobs</a>
+        <a href="{{ url_for('main.admin_jobs') }}">Production Jobs</a>
+        |
+        <a href="{{ url_for('main.admin_inventory') }}">Station Inventory</a>
+        |
+        <a href="{{ url_for('main.warehouse_requests') }}">Warehouse Requests</a>
     </p>
 
     <h1>{{ job.name }}</h1>
@@ -15,6 +19,63 @@
     <p><strong>Production Quantity:</strong> {{ job.quantity }}</p>
     <p><strong>Low-stock Threshold:</strong> {{ job.threshold_percent }}%</p>
 
+    {% if job.status == "Draft" %}
+        <form
+            method="post"
+            action="{{ url_for('main.activate_job_route', job_id=job.id) }}"
+        >
+            <button type="submit">Activate Job</button>
+        </form>
+    {% endif %}
+
+    {% if transfer_requests %}
+        <h2>Transfer Requests</h2>
+
+        <table border="1" cellpadding="8">
+            <tr>
+                <th>Request</th>
+                <th>Station</th>
+                <th>Part</th>
+                <th>Requested</th>
+                <th>Status</th>
+            </tr>
+
+            {% for transfer in transfer_requests %}
+                <tr>
+                    <td>#{{ transfer.id }}</td>
+                    <td>{{ transfer.station.name }}</td>
+                    <td>{{ transfer.part.name }}</td>
+                    <td>{{ transfer.requested_quantity }}</td>
+                    <td>{{ transfer.status }}</td>
+                </tr>
+            {% endfor %}
+        </table>
+    {% endif %}
+
+    {% if job.barcode %}
+        <h2>Job Barcode</h2>
+        <p>
+            <strong>{{ job.barcode }}</strong>
+        </p>
+    {% endif %}
+
+    {% if product_units %}
+        <h2>Product Units</h2>
+
+        <table border="1" cellpadding="8">
+            <tr>
+                <th>Unit</th>
+                <th>Status</th>
+            </tr>
+
+            {% for unit in product_units %}
+                <tr>
+                    <td>{{ unit.unit_number }}</td>
+                    <td>{{ unit.status }}</td>
+                </tr>
+            {% endfor %}
+        </table>
+    {% endif %}
     <h2>Production Steps</h2>
 
     {% if job.steps %}
@@ -22,14 +83,25 @@
             <div>
                 <h3>Step {{ step.step_number }}</h3>
 
-                <p><strong>Station:</strong> {{ step.station.name }}</p>
-                <p><strong>Instruction:</strong> {{ step.instruction }}</p>
+                <p>
+                    <strong>Station:</strong>
+                    {{ step.station.name }}
+                </p>
+
+                <p>
+                    <strong>Instruction:</strong>
+                    {{ step.instruction }}
+                </p>
 
                 {% if step.photo_url %}
-                    <p><strong>Photo:</strong> {{ step.photo_url }}</p>
+                    <p>
+                        <strong>Photo:</strong>
+                        {{ step.photo_url }}
+                    </p>
                 {% endif %}
 
                 <p><strong>Required Parts:</strong></p>
+
                 <ul>
                     {% for usage in step.parts %}
                         <li>
@@ -43,43 +115,55 @@
         <p>No steps added yet.</p>
     {% endif %}
 
-    <hr>
+    {% if job.status == "Draft" %}
+        <hr>
 
-    <h2>Add Production Step</h2>
+        <h2>Add Production Step</h2>
 
-    <form method="post">
-        <p>
-            <label>Station</label><br>
-            <select name="station_id" required>
-                {% for station in stations %}
-                    <option value="{{ station.id }}">
-                        {{ station.id }} - {{ station.name }}
-                    </option>
-                {% endfor %}
-            </select>
-        </p>
+        <form method="post">
+            <p>
+                <label>Station</label><br>
 
-        <p>
-            <label>Instruction</label><br>
-            <textarea name="instruction" required></textarea>
-        </p>
+                <select name="station_id" required>
+                    {% for station in stations %}
+                        <option value="{{ station.id }}">
+                            {{ station.id }} - {{ station.name }}
+                        </option>
+                    {% endfor %}
+                </select>
+            </p>
 
-        <p>
-            <label>Instruction Photo URL</label><br>
-            <input type="text" name="photo_url">
-        </p>
+            <p>
+                <label>Instruction</label><br>
+                <textarea name="instruction" required></textarea>
+            </p>
 
-        <p>
-            <label>Required Part</label><br>
-            <input type="text" name="part_name" required>
-        </p>
+            <p>
+                <label>Instruction Photo URL</label><br>
+                <input type="text" name="photo_url">
+            </p>
+
+            <p>
+                <label>Required Part</label><br>
+                <input type="text" name="part_name" required>
+            </p>
+
+            <p>
+                <label>Part Quantity</label><br>
+                <input
+                    type="number"
+                    name="part_quantity"
+                    min="1"
+                    required
+                >
+            </p>
 
+            <button type="submit">Add Step</button>
+        </form>
+    {% else %}
         <p>
-            <label>Part Quantity</label><br>
-            <input type="number" name="part_quantity" min="1" required>
+            Production configuration is locked because this job is active.
         </p>
-
-        <button type="submit">Add Step</button>
-    </form>
+    {% endif %}
 </body>
 </html>
\ No newline at end of file
diff --git a/app/templates/transfer_requests.html b/app/templates/transfer_requests.html
new file mode 100644
index 0000000000000000000000000000000000000000..e8c675351524b125868c561d1ffde9f6f1ad5482
--- /dev/null
+++ b/app/templates/transfer_requests.html
@@ -0,0 +1,74 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>MES - Warehouse Requests</title>
+</head>
+<body>
+    <p>
+        <a href="{{ url_for('main.admin_jobs') }}">Production Jobs</a>
+        |
+        <a href="{{ url_for('main.admin_inventory') }}">
+            Station Inventory
+        </a>
+    </p>
+
+    <h1>Warehouse Transfer Requests</h1>
+
+<p>Manage station replenishment requests.</p>
+
+    {% if transfer_requests %}
+        <table border="1" cellpadding="8">
+            <tr>
+                <th>Request</th>
+                <th>Job</th>
+                <th>Station</th>
+                <th>Part</th>
+                <th>Requested</th>
+                <th>Transferred</th>
+                <th>Status</th>
+                <th>Action</th>
+            </tr>
+
+            {% for transfer in transfer_requests %}
+                <tr>
+                    <td>#{{ transfer.id }}</td>
+                    <td>{{ transfer.job.name }}</td>
+                    <td>{{ transfer.station.name }}</td>
+                    <td>{{ transfer.part.name }}</td>
+                    <td>{{ transfer.requested_quantity }}</td>
+                    <td>{{ transfer.transferred_quantity }}</td>
+                    <td>{{ transfer.status }}</td>
+
+                    <td>
+                        {% if transfer.status in ["Pending", "Partially Fulfilled"] %}
+                            <form
+                                method="post"
+                                action="{{ url_for(
+                                    'main.fulfill_request_route',
+                                    request_id=transfer.id
+                                ) }}"
+                            >
+                                <input
+                                    type="number"
+                                    name="transferred_quantity"
+                                    min="1"
+                                    value="{{ transfer.requested_quantity - transfer.transferred_quantity }}"
+                                    required
+                                >
+                                <button type="submit">
+                                    Fulfill
+                                </button>
+                            </form>
+                        {% else %}
+                            Completed
+                        {% endif %}
+                    </td>
+                </tr>
+            {% endfor %}
+        </table>
+    {% else %}
+        <p>No transfer requests.</p>
+    {% endif %}
+</body>
+</html>
\ No newline at end of file
diff --git a/tests/test_inventory_activation.py b/tests/test_inventory_activation.py
new file mode 100644
index 0000000000000000000000000000000000000000..66e477f8bd0e925973f9ba4ae44718b2b0ced8b0
--- /dev/null
+++ b/tests/test_inventory_activation.py
@@ -0,0 +1,184 @@
+import pytest
+
+from app import create_app, db
+from app.models import (
+    Job,
+    JobStep,
+    Part,
+    ProductUnit,
+    Station,
+    StationInventory,
+    StepPart,
+    TransferRequest,
+)
+from app.services import (
+    activate_job,
+    fulfill_transfer_request,
+    set_station_inventory,
+)
+
+
+@pytest.fixture
+def app():
+    return create_app(
+        {
+            "TESTING": True,
+            "SQLALCHEMY_DATABASE_URI": "sqlite:///:memory:",
+        }
+    )
+
+
+def create_test_job(app, threshold_percent=20.0):
+    with app.app_context():
+        station = db.session.get(Station, "ST-01")
+
+        part = Part(name="Part A")
+
+        job_data = {
+            "name": "Test Production Job",
+            "quantity": 10,
+            "status": "Draft",
+        }
+
+        if threshold_percent is not None:
+            job_data["threshold_percent"] = threshold_percent
+
+        job = Job(**job_data)
+
+        step = JobStep(
+            job=job,
+            step_number=1,
+            instruction="Attach Part A",
+            station=station,
+        )
+
+        usage = StepPart(
+            step=step,
+            part=part,
+            quantity=1,
+        )
+
+        db.session.add_all([job, part, step, usage])
+        db.session.commit()
+
+        return job.id, part.id
+
+
+def test_tc02_activate_job_with_sufficient_station_stock(app):
+    job_id, part_id = create_test_job(app)
+
+    with app.app_context():
+        set_station_inventory("ST-01", part_id, 10)
+
+        job = db.session.get(Job, job_id)
+
+        result = activate_job(job)
+
+        assert result is True
+        assert job.status == "Active"
+
+        assert TransferRequest.query.count() == 0
+
+        units = ProductUnit.query.filter_by(job_id=job_id).all()
+
+        assert job.barcode is not None
+        assert job.barcode.startswith("MES-")
+        assert len(units) == 10
+
+
+def test_tc03_default_threshold_is_twenty_percent(app):
+    job_id, part_id = create_test_job(
+        app,
+        threshold_percent=None,
+    )
+
+    with app.app_context():
+        job = db.session.get(Job, job_id)
+
+        assert job.threshold_percent == 20.0
+
+        set_station_inventory("ST-01", part_id, 2)
+
+        result = activate_job(job)
+
+        assert result is True
+        assert job.status == "Active"
+        assert TransferRequest.query.count() == 0
+
+
+def test_tc04_duplicate_transfer_request_is_not_created(app):
+    job_id, part_id = create_test_job(app)
+
+    with app.app_context():
+        set_station_inventory("ST-01", part_id, 0)
+
+        job = db.session.get(Job, job_id)
+
+        assert activate_job(job) is False
+        assert activate_job(job) is False
+
+        requests = TransferRequest.query.filter_by(
+            job_id=job_id,
+            station_id="ST-01",
+            part_id=part_id,
+        ).all()
+
+        assert len(requests) == 1
+        assert requests[0].status == "Pending"
+
+
+def test_tc05_insufficient_station_stock_creates_transfer(app):
+    job_id, part_id = create_test_job(app)
+
+    with app.app_context():
+        set_station_inventory("ST-01", part_id, 1)
+
+        job = db.session.get(Job, job_id)
+
+        result = activate_job(job)
+
+        assert result is False
+        assert job.status == "Draft"
+
+        transfer = TransferRequest.query.one()
+
+        assert transfer.station_id == "ST-01"
+        assert transfer.part_id == part_id
+        assert transfer.requested_quantity == 9
+        assert transfer.status == "Pending"
+
+
+def test_tc06_fulfill_station_transfer(app):
+    job_id, part_id = create_test_job(app)
+
+    with app.app_context():
+        set_station_inventory("ST-01", part_id, 1)
+
+        job = db.session.get(Job, job_id)
+
+        activate_job(job)
+
+        transfer = TransferRequest.query.one()
+
+        fulfill_transfer_request(
+            transfer.id,
+            transferred_quantity=9,
+        )
+
+        inventory = StationInventory.query.filter_by(
+            station_id="ST-01",
+            part_id=part_id,
+        ).one()
+
+        transfer = db.session.get(
+            TransferRequest,
+            transfer.id,
+        )
+
+        job = db.session.get(Job, job_id)
+
+        assert inventory.quantity == 10
+        assert transfer.transferred_quantity == 9
+        assert transfer.status == "Fulfilled"
+        assert transfer.completed_at is not None
+        assert job.status == "Active"
\ No newline at end of file