diff --git a/ereuse_devicehub/config.py b/ereuse_devicehub/config.py
index be15650d..b1db6e9e 100644
--- a/ereuse_devicehub/config.py
+++ b/ereuse_devicehub/config.py
@@ -7,7 +7,8 @@ from teal.config import Config
 from teal.enums import Currency
 from teal.utils import import_resource
 
-from ereuse_devicehub.resources import action, agent, deliverynote, inventory, lot, tag, user
+from ereuse_devicehub.resources import action, agent, deliverynote, inventory, \
+    lot, proof, tag, user
 from ereuse_devicehub.resources.device import definitions
 from ereuse_devicehub.resources.documents import documents
 from ereuse_devicehub.resources.enums import PriceSoftware
@@ -21,6 +22,7 @@ class DevicehubConfig(Config):
                                      import_resource(agent),
                                      import_resource(lot),
                                      import_resource(deliverynote),
+                                     import_resource(proof),
                                      import_resource(documents),
                                      import_resource(inventory)),
                                )
diff --git a/ereuse_devicehub/resources/deliverynote/views.py b/ereuse_devicehub/resources/deliverynote/views.py
index 0b0cb35a..02a1ff8b 100644
--- a/ereuse_devicehub/resources/deliverynote/views.py
+++ b/ereuse_devicehub/resources/deliverynote/views.py
@@ -16,6 +16,7 @@ from ereuse_devicehub.db import db
 from ereuse_devicehub.query import things_response
 from ereuse_devicehub.resources.deliverynote.models import Deliverynote
 from ereuse_devicehub.resources.lot.models import Lot
+from ereuse_devicehub.resources.device.models import Computer
 
 
 class DeliverynoteView(View):
@@ -41,8 +42,18 @@ class DeliverynoteView(View):
                                                       'ethereum_address'), partial=True)
         d = request.get_json(schema=patch_schema)
         dlvnote = Deliverynote.query.filter_by(id=id).one()
+        # device_fields = ['transfer_state',  'deliverynote_address']
+        # computers = [x for x in dlvnote.transferred_devices if isinstance(x, Computer)]
         for key, value in d.items():
             setattr(dlvnote, key, value)
+            # Transalate ethereum_address attribute
+            # devKey = key
+            # if key == 'ethereum_address':
+            #     devKey = 'deliverynote_address'
+            # if devKey in device_fields:
+            #     for dev in computers:
+            #         setattr(dev, devKey, value)
+         
         db.session.commit()
         return Response(status=204)
 
diff --git a/ereuse_devicehub/resources/device/models.py b/ereuse_devicehub/resources/device/models.py
index 1ecbe8f3..68134b8e 100644
--- a/ereuse_devicehub/resources/device/models.py
+++ b/ereuse_devicehub/resources/device/models.py
@@ -382,6 +382,7 @@ class Computer(Device):
 
     It is a subset of the Linux definition of DMI / DMI decode.
     """
+    ethereum_address = Column(CIText(), unique=True, default=None)
     deposit = Column(Integer, check_range('deposit',min=0,max=100), default=0)
     owner_address = db.Column(CIText(),
                           db.ForeignKey(User.ethereum_address),
diff --git a/ereuse_devicehub/resources/device/schemas.py b/ereuse_devicehub/resources/device/schemas.py
index 093cec75..61c399ad 100644
--- a/ereuse_devicehub/resources/device/schemas.py
+++ b/ereuse_devicehub/resources/device/schemas.py
@@ -122,6 +122,7 @@ class Computer(Device):
                        dump_only=True,
                        collection_class=set,
                        description=m.Computer.privacy.__doc__)
+    ethereum_address = SanitizedStr(validate=f.validate.Length(max=42))
     deposit = Integer(validate=f.validate.Range(min=0, max=100),
                        description=m.Computer.deposit.__doc__)
     # author_id = NestedOn(s_user.User,only_query='author_id')
diff --git a/ereuse_devicehub/resources/device/views.py b/ereuse_devicehub/resources/device/views.py
index 665acd68..1aaa1f93 100644
--- a/ereuse_devicehub/resources/device/views.py
+++ b/ereuse_devicehub/resources/device/views.py
@@ -1,10 +1,10 @@
 import datetime
 
 import marshmallow
-from flask import current_app as app, render_template, request
+from flask import current_app as app, render_template, request, Response
 from flask.json import jsonify
 from flask_sqlalchemy import Pagination
-from marshmallow import fields, fields as f, validate as v
+from marshmallow import fields, fields as f, validate as v, ValidationError
 from teal import query
 from teal.cache import cache
 from teal.resource import View
@@ -15,7 +15,7 @@ from ereuse_devicehub.query import SearchQueryParser, things_response
 from ereuse_devicehub.resources import search
 from ereuse_devicehub.resources.action import models as actions
 from ereuse_devicehub.resources.device import states
-from ereuse_devicehub.resources.device.models import Device, Manufacturer
+from ereuse_devicehub.resources.device.models import Device, Manufacturer, Computer
 from ereuse_devicehub.resources.device.search import DeviceSearch
 from ereuse_devicehub.resources.lot.models import LotDeviceDescendants
 from ereuse_devicehub.resources.tag.model import Tag
@@ -92,7 +92,24 @@ class DeviceView(View):
             description: The device or devices.
         """
         return super().get(id)
-
+        
+    def patch(self, id):
+        dev = Device.query.filter_by(id=id).one()
+        if isinstance(dev, Computer):
+            resource_def = app.resources['Computer']
+            # TODO check how to handle the 'actions_one'
+            patch_schema = resource_def.SCHEMA(only=['ethereum_address', 'transfer_state', 'deliverynote_address', 'actions_one'], partial=True)
+            json = request.get_json(schema=patch_schema)
+            # TODO check how to handle the 'actions_one'
+            json.pop('actions_one')
+            if not dev:
+                raise ValueError('Device non existent')
+            for key, value in json.items():
+                setattr(dev,key,value)
+            db.session.commit()
+            return Response(status=204)
+        raise ValueError('Cannot patch a non computer')
+    
     def one(self, id: int):
         """Gets one device."""
         if not request.authorization:
diff --git a/ereuse_devicehub/resources/proof/__init__.py b/ereuse_devicehub/resources/proof/__init__.py
new file mode 100644
index 00000000..ef3a68a6
--- /dev/null
+++ b/ereuse_devicehub/resources/proof/__init__.py
@@ -0,0 +1,37 @@
+from teal.resource import Converters, Resource
+
+from ereuse_devicehub.resources.proof import schemas
+from ereuse_devicehub.resources.proof.views import ProofView
+
+
+class ProofDef(Resource):
+    SCHEMA = schemas.Proof
+    VIEW = ProofView
+    # AUTH = True
+    AUTH = False
+    ID_CONVERTER = Converters.uuid
+
+
+class ProofTransferDef(ProofDef):
+    VIEW = None
+    SCHEMA = schemas.ProofTransfer
+
+
+class ProofDataWipeDef(ProofDef):
+    VIEW = None
+    SCHEMA = schemas.ProofDataWipe
+
+
+class ProofFunction(ProofDef):
+    VIEW = None
+    SCHEMA = schemas.ProofFunction
+
+
+class ProofReuse(ProofDef):
+    VIEW = None
+    SCHEMA = schemas.ProofReuse
+
+
+class ProofRecycling(ProofDef):
+    VIEW = None
+    SCHEMA = schemas.ProofRecycling
diff --git a/ereuse_devicehub/resources/proof/models.py b/ereuse_devicehub/resources/proof/models.py
new file mode 100644
index 00000000..2562b446
--- /dev/null
+++ b/ereuse_devicehub/resources/proof/models.py
@@ -0,0 +1,158 @@
+"""This file contains all proofs related to actions
+
+"""
+
+from collections import Iterable
+from datetime import datetime
+from typing import Optional, Set, Union
+from uuid import uuid4
+
+from boltons import urlutils
+from citext import CIText
+from flask import current_app as app, g
+from sortedcontainers import SortedSet
+from sqlalchemy import BigInteger, Column, Enum as DBEnum, \
+    ForeignKey, Integer, Unicode
+from sqlalchemy.dialects.postgresql import UUID
+from sqlalchemy.ext.declarative import declared_attr
+from sqlalchemy.ext.orderinglist import ordering_list
+from sqlalchemy.orm import backref, relationship, validates
+from sqlalchemy.util import OrderedSet
+from teal.db import CASCADE_OWN, INHERIT_COND, POLYMORPHIC_ID, \
+    POLYMORPHIC_ON, StrictVersionType, URL
+from teal.marshmallow import ValidationError
+from teal.resource import url_for_resource
+
+from ereuse_devicehub.db import db
+from ereuse_devicehub.resources.action.models import Action, DisposeProduct, \
+    EraseBasic, Rate, Trade
+from ereuse_devicehub.resources.device.models import Device
+from ereuse_devicehub.resources.models import Thing
+from ereuse_devicehub.resources.user import User
+
+
+class JoinedTableMixin:
+    # noinspection PyMethodParameters
+    @declared_attr
+    def id(cls):
+        return Column(UUID(as_uuid=True), ForeignKey(Proof.id), primary_key=True)
+
+
+class Proof(Thing):
+    """Proof over an action.
+
+    """
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid4)
+    type = Column(Unicode, nullable=False)
+    ethereum_hash = Column(CIText(), default='', nullable=False)
+    device_id = db.Column(BigInteger,
+                          db.ForeignKey(Device.id),
+                          nullable=False)
+    device = db.relationship(Device,
+                             backref=db.backref('proofs_device', uselist=True, lazy=True),
+                             lazy=True,
+                             primaryjoin=Device.id == device_id)
+
+    @property
+    def url(self) -> urlutils.URL:
+        """The URL where to GET this proof."""
+        return urlutils.URL(url_for_resource(Proof, item_id=self.id))
+
+    # noinspection PyMethodParameters
+    @declared_attr
+    def __mapper_args__(cls):
+        """Defines inheritance.
+
+        From `the guide <http://docs.sqlalchemy.org/en/latest/orm/
+        extensions/declarative/api.html
+        #sqlalchemy.ext.declarative.declared_attr>`_
+        """
+        args = {POLYMORPHIC_ID: cls.t}
+        if cls.t == 'Proof':
+            args[POLYMORPHIC_ON] = cls.type
+        # noinspection PyUnresolvedReferences
+        if JoinedTableMixin in cls.mro():
+            args[INHERIT_COND] = cls.id == Proof.id
+        return args
+
+    def __init__(self, **kwargs) -> None:
+        # sortedset forces us to do this before calling our parent init
+        super().__init__(**kwargs)
+
+    def __repr__(self):
+        return '<{0.t} {0.id} >'.format(self)
+
+
+
+class ProofTransfer(JoinedTableMixin, Proof):
+    supplier_id = db.Column(UUID(as_uuid=True),
+                         db.ForeignKey(User.id),
+                         nullable=False,
+                         default=lambda: g.user.id)
+    supplier = db.relationship(User, primaryjoin=lambda: ProofTransfer.supplier_id == User.id)
+    receiver_id = db.Column(UUID(as_uuid=True),
+                         db.ForeignKey(User.id),
+                         nullable=False)
+    receiver = db.relationship(User, primaryjoin=lambda: ProofTransfer.receiver_id == User.id)
+    deposit = Column(db.Integer, default=0)
+
+
+class ProofDataWipe(JoinedTableMixin, Proof):
+    # erasure_type = Column(CIText(), default='', nullable=False)
+    date = Column(db.DateTime, nullable=False, default=datetime.utcnow)
+    result = Column(db.Boolean, default=False, nullable=False)
+    result.comment = """Identifies proof datawipe as a result."""
+    proof_author_id = Column(UUID(as_uuid=True),
+                          db.ForeignKey(User.id),
+                          nullable=False,
+                          default=lambda: g.user.id)
+    proof_author = relationship(User, primaryjoin=lambda: ProofDataWipe.proof_author_id == User.id)
+    erasure_id = Column(UUID(as_uuid=True), ForeignKey(EraseBasic.id), nullable=False)
+    erasure = relationship(EraseBasic,
+                           backref=backref('proof_datawipe',
+                                           lazy=True,
+                                           uselist=False,
+                                           cascade=CASCADE_OWN),
+                           primaryjoin=EraseBasic.id == erasure_id)
+
+
+class ProofFunction(JoinedTableMixin, Proof):
+    disk_usage = Column(db.Integer, default=0)
+    proof_author_id = Column(UUID(as_uuid=True),
+                          db.ForeignKey(User.id),
+                          nullable=False,
+                          default=lambda: g.user.id)
+    proof_author = db.relationship(User, primaryjoin=lambda: ProofFunction.proof_author_id == User.id)
+    rate_id = Column(UUID(as_uuid=True), ForeignKey(Rate.id), nullable=False)
+    rate = relationship(Rate,
+                       backref=backref('proof_function',
+                                       lazy=True,
+                                       uselist=False,
+                                       cascade=CASCADE_OWN),
+                        primaryjoin=Rate.id == rate_id)
+
+
+class ProofReuse(JoinedTableMixin, Proof):
+    receiver_segment = Column(CIText(), default='', nullable=False)
+    id_receipt = Column(CIText(), default='', nullable=False)
+    supplier_id = db.Column(UUID(as_uuid=True),
+                         db.ForeignKey(User.id),
+                         # nullable=False,
+                         # default=lambda: g.user.id)
+                         nullable=True)
+    supplier = db.relationship(User, primaryjoin=lambda: ProofReuse.supplier_id == User.id)
+    receiver_id = db.Column(UUID(as_uuid=True),
+                         db.ForeignKey(User.id),
+                         # nullable=False)
+                         nullable=True)
+    receiver = db.relationship(User, primaryjoin=lambda: ProofReuse.receiver_id == User.id)
+    price = Column(db.Integer)
+
+
+class ProofRecycling(JoinedTableMixin, Proof):
+    collection_point = Column(CIText(), default='', nullable=False)
+    date = Column(db.DateTime, nullable=False, default=datetime.utcnow)
+    contact = Column(CIText(), default='', nullable=False)
+    ticket = Column(CIText(), default='', nullable=False)
+    gps_location = Column(CIText(), default='', nullable=False)
+    recycler_code = Column(CIText(), default='', nullable=False)
diff --git a/ereuse_devicehub/resources/proof/schemas.py b/ereuse_devicehub/resources/proof/schemas.py
new file mode 100644
index 00000000..de18a41f
--- /dev/null
+++ b/ereuse_devicehub/resources/proof/schemas.py
@@ -0,0 +1,72 @@
+from flask import current_app as app
+from marshmallow import Schema as MarshmallowSchema, ValidationError, fields as f, validates_schema
+from marshmallow.fields import Boolean, DateTime, Integer, Nested, String, UUID
+from marshmallow.validate import Length
+from sqlalchemy.util import OrderedSet
+from teal.marshmallow import SanitizedStr, URL
+from teal.resource import Schema
+
+from ereuse_devicehub.marshmallow import NestedOn
+from ereuse_devicehub.resources.proof import models as m
+from ereuse_devicehub.resources.models import STR_BIG_SIZE, STR_SIZE
+from ereuse_devicehub.resources.schemas import Thing
+from ereuse_devicehub.resources.action import schemas as s_action
+from ereuse_devicehub.resources.device import schemas as s_device
+from ereuse_devicehub.resources.user import schemas as s_user
+
+
+class Proof(Thing):
+    __doc__ = m.Proof.__doc__
+    id = UUID(dump_only=True)
+    ethereum_hash = SanitizedStr(default='', validate=Length(max=STR_BIG_SIZE),
+                                   data_key="ethereumHash", required=True)
+    url = URL(dump_only=True, description=m.Proof.url.__doc__)
+    device_id = Integer(load_only=True, data_key='deviceID')
+    device = NestedOn(s_device.Device, dump_only=True)
+
+
+class ProofTransfer(Proof):
+    __doc__ = m.ProofTransfer.__doc__
+    deposit = Integer(validate=f.validate.Range(min=0, max=100))
+    supplier_id = UUID(load_only=True, required=True, data_key='supplierID')
+    receiver_id = UUID(load_only=True, required=True, data_key='receiverID')
+
+
+class ProofDataWipe(Proof):
+    __doc__ = m.ProofDataWipe.__doc__
+    # erasure_type = String(default='', data_key='erasureType')
+    date = DateTime('iso', required=True)
+    result = Boolean(required=True)
+    proof_author_id = SanitizedStr(validate=f.validate.Length(max=STR_SIZE),
+                                   load_only=True, required=True, data_key='proofAuthorID')
+    proof_author = NestedOn(s_user.User, dump_only=True)
+    erasure = NestedOn(s_action.EraseBasic, only_query='id', data_key='erasureID')
+
+
+class ProofFunction(Proof):
+    __doc__ = m.ProofFunction.__doc__
+    disk_usage = Integer(validate=f.validate.Range(min=0, max=100), data_key='diskUsage')
+    proof_author_id = SanitizedStr(validate=f.validate.Length(max=STR_SIZE),
+                                   load_only=True, required=True, data_key='proofAuthorID')
+    proof_author = NestedOn(s_user.User, dump_only=True)
+    rate = NestedOn(s_action.Rate, required=True,
+                    only_query='id', data_key='rateID')
+
+
+class ProofReuse(Proof):
+    __doc__ = m.ProofReuse.__doc__
+    receiver_segment = String(default='', data_key='receiverSegment', required=True)
+    id_receipt = String(default='', data_key='idReceipt', required=True)
+    supplier_id = UUID(load_only=True, required=False, data_key='supplierID')
+    receiver_id = UUID(load_only=True, required=False, data_key='receiverID')
+    price = Integer(required=True)
+
+
+class ProofRecycling(Proof):
+    __doc__ = m.ProofRecycling.__doc__
+    collection_point = SanitizedStr(default='', data_key='collectionPoint', required=True)
+    date = DateTime('iso', required=True)
+    contact = SanitizedStr(default='', required=True)
+    ticket = SanitizedStr(default='', required=True)
+    gps_location = SanitizedStr(default='', data_key='gpsLocation', required=True)
+    recycler_code = SanitizedStr(default='', data_key='recyclerCode', required=True)
diff --git a/ereuse_devicehub/resources/proof/views.py b/ereuse_devicehub/resources/proof/views.py
new file mode 100644
index 00000000..9b016df9
--- /dev/null
+++ b/ereuse_devicehub/resources/proof/views.py
@@ -0,0 +1,44 @@
+from distutils.version import StrictVersion
+from typing import List
+from uuid import UUID
+
+from flask import current_app as app, request, jsonify
+from sqlalchemy.util import OrderedSet
+from teal.marshmallow import ValidationError
+from teal.resource import View
+
+from ereuse_devicehub.db import db
+from ereuse_devicehub.query import things_response
+from ereuse_devicehub.resources.action.models import Action, RateComputer, Snapshot, VisualTest
+from ereuse_devicehub.resources.action.rate.v1_0 import CannotRate
+from ereuse_devicehub.resources.device.models import Component, Computer
+from ereuse_devicehub.resources.enums import SnapshotSoftware
+
+SUPPORTED_WORKBENCH = StrictVersion('11.0')
+
+
+class ProofView(View):
+    def post(self):
+        """Posts batches of proofs."""
+        json = request.get_json(validate=False)
+        if not json:
+            raise ValidationError('JSON is not correct.')
+        # todo there should be a way to better get subclassess resource
+        #   defs
+        proofs = list()
+        if json['batch']:
+            for prf in json['proofs']:
+                resource_def = app.resources[prf['type']]
+                p = resource_def.schema.load(prf)
+                Model = db.Model._decl_class_registry.data[prf['type']]()
+                proof = Model(**p)
+                db.session.add(proof)
+                proofs.append(resource_def.schema.dump(proof))
+            db.session().final_flush()
+            db.session.commit()
+            response = jsonify({
+                'items': proofs,
+                'url': request.path
+            })
+            response.status_code = 201
+            return response