diff --git a/tensorflow/python/frozen_keras/engine/BUILD b/tensorflow/python/frozen_keras/engine/BUILD
index e94a8d63fb9..6e7f1f4a8c2 100644
--- a/tensorflow/python/frozen_keras/engine/BUILD
+++ b/tensorflow/python/frozen_keras/engine/BUILD
@@ -12,6 +12,8 @@ py_library(
     srcs = ["legacy_base_layer.py"],
     deps = [
         ":base_layer_utils",
+        ":input_spec",
+        ":node",
         "//tensorflow/core:protos_all_py",
         "//tensorflow/python:array_ops",
         "//tensorflow/python:auto_control_deps",
@@ -38,7 +40,6 @@ py_library(
         "//tensorflow/python/keras:backend",
         "//tensorflow/python/keras:metrics",
         "//tensorflow/python/keras/engine",
-        "//tensorflow/python/keras/engine:input_spec",
         "//tensorflow/python/keras/saving",
         "//tensorflow/python/keras/utils:generic_utils",
         "//tensorflow/python/keras/utils:layer_utils",
@@ -78,6 +79,31 @@ py_library(
     ],
 )
 
+py_library(
+    name = "input_spec",
+    srcs = ["input_spec.py"],
+    srcs_version = "PY2AND3",
+    deps = [
+        "//tensorflow/python:dtypes",
+        "//tensorflow/python:lib",
+        "//tensorflow/python:tensor_shape",
+        "//tensorflow/python:tensor_spec",
+        "//tensorflow/python/keras:backend",
+        "@six_archive//:six",
+    ],
+)
+
+py_library(
+    name = "node",
+    srcs = ["node.py"],
+    deps = [
+        ":base_layer_utils",
+        "//tensorflow/python:framework_ops",
+        "//tensorflow/python:util",
+        "//tensorflow/python/keras:backend",
+    ],
+)
+
 tf_py_test(
     name = "legacy_base_layer_test",
     size = "medium",
@@ -110,3 +136,18 @@ tf_py_test(
         "@absl_py//absl/testing:parameterized",
     ],
 )
+
+tf_py_test(
+    name = "input_spec_test",
+    size = "small",
+    srcs = ["input_spec_test.py"],
+    python_version = "PY3",
+    tags = [
+        "nomac",  # TODO(mihaimaruseac): b/127695564
+    ],
+    deps = [
+        ":input_spec",
+        "//tensorflow/python:client_testlib",
+        "@absl_py//absl/testing:parameterized",
+    ],
+)
diff --git a/tensorflow/python/frozen_keras/engine/input_spec.py b/tensorflow/python/frozen_keras/engine/input_spec.py
new file mode 100644
index 00000000000..9d54a2d3719
--- /dev/null
+++ b/tensorflow/python/frozen_keras/engine/input_spec.py
@@ -0,0 +1,233 @@
+# Copyright 2018 The TensorFlow Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+# pylint: disable=protected-access
+# pylint: disable=g-classes-have-attributes
+"""Contains the InputSpec class."""
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from six.moves import zip  # pylint: disable=redefined-builtin
+
+from tensorflow.python.framework import dtypes
+from tensorflow.python.framework import tensor_shape
+from tensorflow.python.framework import tensor_spec
+from tensorflow.python.keras import backend
+from tensorflow.python.util import nest
+
+
+class InputSpec(object):
+  """Specifies the rank, dtype and shape of every input to a layer.
+
+  Layers can expose (if appropriate) an `input_spec` attribute:
+  an instance of `InputSpec`, or a nested structure of `InputSpec` instances
+  (one per input tensor). These objects enable the layer to run input
+  compatibility checks for input structure, input rank, input shape, and
+  input dtype.
+
+  A None entry in a shape is compatible with any dimension,
+  a None shape is compatible with any shape.
+
+  Arguments:
+      dtype: Expected DataType of the input.
+      shape: Shape tuple, expected shape of the input
+          (may include None for unchecked axes).
+      ndim: Integer, expected rank of the input.
+      max_ndim: Integer, maximum rank of the input.
+      min_ndim: Integer, minimum rank of the input.
+      axes: Dictionary mapping integer axes to
+          a specific dimension value.
+  """
+
+  def __init__(self,
+               dtype=None,
+               shape=None,
+               ndim=None,
+               max_ndim=None,
+               min_ndim=None,
+               axes=None):
+    self.dtype = dtypes.as_dtype(dtype).name if dtype is not None else None
+    if shape is not None:
+      self.ndim = len(shape)
+      self.shape = shape
+    else:
+      self.ndim = ndim
+      self.shape = None
+    self.max_ndim = max_ndim
+    self.min_ndim = min_ndim
+    try:
+      axes = axes or {}
+      self.axes = {int(k): axes[k] for k in axes}
+    except (ValueError, TypeError):
+      raise TypeError('The keys in axes must be integers.')
+
+    if self.axes and (self.ndim is not None or self.max_ndim is not None):
+      max_dim = (self.ndim if self.ndim else self.max_ndim) - 1
+      max_axis = max(self.axes)
+      if max_axis > max_dim:
+        raise ValueError('Axis {} is greater than the maximum allowed value: {}'
+                         .format(max_axis, max_dim))
+
+  def __repr__(self):
+    spec = [('dtype=' + str(self.dtype)) if self.dtype else '',
+            ('shape=' + str(self.shape)) if self.shape else '',
+            ('ndim=' + str(self.ndim)) if self.ndim else '',
+            ('max_ndim=' + str(self.max_ndim)) if self.max_ndim else '',
+            ('min_ndim=' + str(self.min_ndim)) if self.min_ndim else '',
+            ('axes=' + str(self.axes)) if self.axes else '']
+    return 'InputSpec(%s)' % ', '.join(x for x in spec if x)
+
+  def get_config(self):
+    return {
+        'dtype': self.dtype,
+        'shape': self.shape,
+        'ndim': self.ndim,
+        'max_ndim': self.max_ndim,
+        'min_ndim': self.min_ndim,
+        'axes': self.axes}
+
+  @classmethod
+  def from_config(cls, config):
+    return cls(**config)
+
+
+def to_tensor_shape(spec):
+  """Returns a tf.TensorShape object that matches the shape specifications.
+
+  If the InputSpec's shape or ndim is defined, this method will return a fully
+  or partially-known shape. Otherwise, the returned TensorShape is None.
+
+  Args:
+    spec: an InputSpec object.
+
+  Returns:
+    a tf.TensorShape object
+  """
+  if spec.ndim is None and spec.shape is None:
+    return tensor_shape.TensorShape(None)
+  elif spec.shape is not None:
+    return tensor_shape.TensorShape(spec.shape)
+  else:
+    shape = [None] * spec.ndim
+    for a in spec.axes:
+      shape[a] = spec.axes[a]  # Assume that axes is defined
+    return tensor_shape.TensorShape(shape)
+
+
+def assert_input_compatibility(input_spec, inputs, layer_name):
+  """Checks compatibility between the layer and provided inputs.
+
+  This checks that the tensor(s) `inputs` verify the input assumptions
+  of a layer (if any). If not, a clear and actional exception gets raised.
+
+  Arguments:
+      input_spec: An InputSpec instance, list of InputSpec instances, a nested
+          structure of InputSpec instances, or None.
+      inputs: Input tensor, list of input tensors, or a nested structure of
+          input tensors.
+      layer_name: String, name of the layer (for error message formatting).
+
+  Raises:
+      ValueError: in case of mismatch between
+          the provided inputs and the expectations of the layer.
+  """
+  if not input_spec:
+    return
+
+  inputs = nest.flatten(inputs)
+  input_spec = nest.flatten(input_spec)
+  if len(inputs) != len(input_spec):
+    raise ValueError('Layer ' + layer_name + ' expects ' +
+                     str(len(input_spec)) + ' inputs, '
+                     'but it received ' + str(len(inputs)) +
+                     ' input tensors. Inputs received: ' + str(inputs))
+  for input_index, (x, spec) in enumerate(zip(inputs, input_spec)):
+    if spec is None:
+      continue
+
+    if (spec.ndim is not None or
+        spec.min_ndim is not None or
+        spec.max_ndim is not None):
+      if x.shape.ndims is None:
+        raise ValueError('Input ' + str(input_index) + ' of layer ' +
+                         layer_name + ' is incompatible with the layer: '
+                         'its rank is undefined, but the layer requires a '
+                         'defined rank.')
+
+    # Check ndim.
+    if spec.ndim is not None:
+      ndim = x.shape.ndims
+      if ndim != spec.ndim:
+        raise ValueError('Input ' + str(input_index) + ' of layer ' +
+                         layer_name + ' is incompatible with the layer: '
+                         'expected ndim=' + str(spec.ndim) + ', found ndim=' +
+                         str(ndim) + '. Full shape received: ' +
+                         str(x.shape.as_list()))
+    if spec.max_ndim is not None:
+      ndim = x.shape.ndims
+      if ndim is not None and ndim > spec.max_ndim:
+        raise ValueError('Input ' + str(input_index) + ' of layer ' +
+                         layer_name + ' is incompatible with the layer: '
+                         'expected max_ndim=' + str(spec.max_ndim) +
+                         ', found ndim=' + str(ndim))
+    if spec.min_ndim is not None:
+      ndim = x.shape.ndims
+      if ndim is not None and ndim < spec.min_ndim:
+        raise ValueError('Input ' + str(input_index) + ' of layer ' +
+                         layer_name + ' is incompatible with the layer: '
+                         ': expected min_ndim=' + str(spec.min_ndim) +
+                         ', found ndim=' + str(ndim) +
+                         '. Full shape received: ' +
+                         str(x.shape.as_list()))
+    # Check dtype.
+    if spec.dtype is not None:
+      if x.dtype != spec.dtype:
+        raise ValueError('Input ' + str(input_index) + ' of layer ' +
+                         layer_name + ' is incompatible with the layer: '
+                         'expected dtype=' + str(spec.dtype) +
+                         ', found dtype=' + str(x.dtype))
+    # Check specific shape axes.
+    if spec.axes:
+      shape = x.shape.as_list()
+      if shape is not None:
+        for axis, value in spec.axes.items():
+          if hasattr(value, 'value'):
+            value = value.value
+          if value is not None and shape[int(axis)] not in {value, None}:
+            raise ValueError(
+                'Input ' + str(input_index) + ' of layer ' + layer_name + ' is'
+                ' incompatible with the layer: expected axis ' + str(axis) +
+                ' of input shape to have value ' + str(value) +
+                ' but received input with shape ' + str(shape))
+    # Check shape.
+    if spec.shape is not None:
+      shape = x.shape.as_list()
+      if shape is not None:
+        for spec_dim, dim in zip(spec.shape, shape):
+          if spec_dim is not None and dim is not None:
+            if spec_dim != dim:
+              raise ValueError('Input ' + str(input_index) +
+                               ' is incompatible with layer ' + layer_name +
+                               ': expected shape=' + str(spec.shape) +
+                               ', found shape=' + str(shape))
+
+
+def to_tensor_spec(input_spec, default_dtype=None):
+  """Converts a Keras InputSpec object to a TensorSpec."""
+  default_dtype = default_dtype or backend.floatx()
+  if isinstance(input_spec, InputSpec):
+    dtype = input_spec.dtype or default_dtype
+    return tensor_spec.TensorSpec(to_tensor_shape(input_spec), dtype)
+  return tensor_spec.TensorSpec(None, default_dtype)
diff --git a/tensorflow/python/frozen_keras/engine/input_spec_test.py b/tensorflow/python/frozen_keras/engine/input_spec_test.py
new file mode 100644
index 00000000000..17423a14886
--- /dev/null
+++ b/tensorflow/python/frozen_keras/engine/input_spec_test.py
@@ -0,0 +1,66 @@
+# Copyright 2019 The TensorFlow Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""InputSpec tests."""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from tensorflow.python.frozen_keras.engine import input_spec
+from tensorflow.python.platform import test
+
+
+class InputSpecTest(test.TestCase):
+
+  def test_axes_initialization(self):
+    input_spec.InputSpec(shape=[1, None, 2, 3], axes={3: 5, '2': 2})
+    with self.assertRaisesRegexp(ValueError, 'Axis 4 is greater than'):
+      input_spec.InputSpec(shape=[1, None, 2, 3], axes={4: 5})
+    with self.assertRaisesRegexp(TypeError, 'keys in axes must be integers'):
+      input_spec.InputSpec(shape=[1, None, 2, 3], axes={'string': 5})
+
+
+class InputSpecToTensorShapeTest(test.TestCase):
+
+  def test_defined_shape(self):
+    spec = input_spec.InputSpec(shape=[1, None, 2, 3])
+    self.assertAllEqual(
+        [1, None, 2, 3], input_spec.to_tensor_shape(spec).as_list())
+
+  def test_defined_ndims(self):
+    spec = input_spec.InputSpec(ndim=5)
+    self.assertAllEqual(
+        [None] * 5, input_spec.to_tensor_shape(spec).as_list())
+
+    spec = input_spec.InputSpec(ndim=0)
+    self.assertAllEqual(
+        [], input_spec.to_tensor_shape(spec).as_list())
+
+    spec = input_spec.InputSpec(ndim=3, axes={1: 3, -1: 2})
+    self.assertAllEqual(
+        [None, 3, 2], input_spec.to_tensor_shape(spec).as_list())
+
+  def test_undefined_shapes(self):
+    spec = input_spec.InputSpec(max_ndim=5)
+    with self.assertRaisesRegexp(ValueError, 'unknown TensorShape'):
+      input_spec.to_tensor_shape(spec).as_list()
+
+    spec = input_spec.InputSpec(min_ndim=5, max_ndim=5)
+    with self.assertRaisesRegexp(ValueError, 'unknown TensorShape'):
+      input_spec.to_tensor_shape(spec).as_list()
+
+
+if __name__ == '__main__':
+  test.main()
diff --git a/tensorflow/python/frozen_keras/engine/legacy_base_layer.py b/tensorflow/python/frozen_keras/engine/legacy_base_layer.py
index f0d195b3a94..d010a370191 100644
--- a/tensorflow/python/frozen_keras/engine/legacy_base_layer.py
+++ b/tensorflow/python/frozen_keras/engine/legacy_base_layer.py
@@ -54,10 +54,10 @@ from tensorflow.python.framework import tensor_util
 from tensorflow.python.frozen_keras import constraints
 from tensorflow.python.frozen_keras import initializers
 from tensorflow.python.frozen_keras import regularizers
+from tensorflow.python.frozen_keras.engine import base_layer_utils
+from tensorflow.python.frozen_keras.engine import input_spec
+from tensorflow.python.frozen_keras.engine import node as node_module
 from tensorflow.python.keras import backend
-from tensorflow.python.keras.engine import base_layer_utils
-from tensorflow.python.keras.engine import input_spec
-from tensorflow.python.keras.engine import node as node_module
 from tensorflow.python.keras.saving.saved_model import layer_serialization
 from tensorflow.python.keras.utils import generic_utils
 from tensorflow.python.keras.utils import layer_utils
diff --git a/tensorflow/python/frozen_keras/engine/node.py b/tensorflow/python/frozen_keras/engine/node.py
new file mode 100644
index 00000000000..9ea8470e31f
--- /dev/null
+++ b/tensorflow/python/frozen_keras/engine/node.py
@@ -0,0 +1,189 @@
+# Copyright 2015 The TensorFlow Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+# pylint: disable=protected-access
+"""Contains the `Node` class."""
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from tensorflow.python.framework import ops
+from tensorflow.python.frozen_keras.engine import base_layer_utils
+from tensorflow.python.keras import backend
+from tensorflow.python.util import nest
+
+
+class Node(object):
+  """A `Node` describes the connectivity between two layers.
+
+  Each time a layer is connected to some new input,
+  a node is added to `layer._inbound_nodes`.
+  Each time the output of a layer is used by another layer,
+  a node is added to `layer._outbound_nodes`.
+
+  Arguments:
+      outbound_layer: the layer that takes
+          `input_tensors` and turns them into `output_tensors`
+          (the node gets created when the `call`
+          method of the layer was called).
+      inbound_layers: a list of layers, the same length as `input_tensors`,
+          the layers from where `input_tensors` originate.
+      node_indices: a list of integers, the same length as `inbound_layers`.
+          `node_indices[i]` is the origin node of `input_tensors[i]`
+          (necessary since each inbound layer might have several nodes,
+          e.g. if the layer is being shared with a different data stream).
+      tensor_indices: a list of integers,
+          the same length as `inbound_layers`.
+          `tensor_indices[i]` is the index of `input_tensors[i]` within the
+          output of the inbound layer
+          (necessary since each inbound layer might
+          have multiple tensor outputs, with each one being
+          independently manipulable).
+      input_tensors: list of input tensors.
+      output_tensors: list of output tensors.
+      arguments: dictionary of keyword arguments that were passed to the
+          `call` method of the layer at the call that created the node.
+
+  `node_indices` and `tensor_indices` are basically fine-grained coordinates
+  describing the origin of the `input_tensors`.
+
+  A node from layer A to layer B is added to:
+    - A._outbound_nodes
+    - B._inbound_nodes
+  """
+
+  def __init__(self,
+               outbound_layer,
+               inbound_layers,
+               node_indices,
+               tensor_indices,
+               input_tensors,
+               output_tensors,
+               arguments=None):
+    # Layer instance (NOT a sequence)
+    if isinstance(outbound_layer, (list, tuple, dict)):
+      raise ValueError('`outbound_layer` should be a layer instance, '
+                       'not a list, tuple, or, dict.')
+
+    # this is the layer that takes a nested structure of input tensors
+    # and turns them into a nested structure of output tensors.
+    # the current node will be added to
+    # the inbound_nodes of outbound_layer.
+    self.outbound_layer = outbound_layer
+
+    # The following 3 properties describe where
+    # the input tensors come from: which layers,
+    # and for each layer, which node and which
+    # tensor output of each node.
+
+    # Nested structure of layer instances.
+    self.inbound_layers = inbound_layers
+    # Nested structure of integers, 1:1 mapping with inbound_layers.
+    self.node_indices = node_indices
+    # Nested of integers, 1:1 mapping with inbound_layers.
+    self.tensor_indices = tensor_indices
+
+    # Following 2 properties:
+    # tensor inputs and outputs of outbound_layer.
+
+    # Nested structure of tensors. 1:1 mapping with inbound_layers.
+    self.input_tensors = input_tensors
+    # Nested structure of tensors, created by outbound_layer.call().
+    self.output_tensors = output_tensors
+
+    # Following 2 properties: input and output shapes.
+
+    # Nested structure of shape tuples, shapes of input_tensors.
+    self.input_shapes = nest.map_structure(backend.int_shape, input_tensors)
+    # Nested structure of shape tuples, shapes of output_tensors.
+    self.output_shapes = nest.map_structure(backend.int_shape, output_tensors)
+
+    # Optional keyword arguments to layer's `call`.
+    self.arguments = arguments
+
+    # Create Keras History for any Keras Tensors in `arguments`.
+    tensor_arguments = [
+        t for t in nest.flatten(self.arguments) if isinstance(t, ops.Tensor)
+    ]
+    for tensor_argument in tensor_arguments:
+      if base_layer_utils.needs_keras_history(
+          tensor_argument, ignore_call_context=True):
+        base_layer_utils.create_keras_history(tensor_argument)
+
+    # Add nodes to all layers involved.
+    for layer in nest.flatten(inbound_layers):
+      if layer is not None:
+        # For compatibility with external Keras, we use the deprecated
+        # accessor here.
+        layer.outbound_nodes.append(self)
+    # For compatibility with external Keras, we use the deprecated
+    # accessor here.
+    outbound_layer.inbound_nodes.append(self)
+
+  def iterate_inbound(self, include_arguments=False):
+    """Returns a list of tuples representing the inbound data.
+
+    Arguments:
+      include_arguments: Whether to also iterate over any Keras Tensors
+        passed as args, kwargs.
+
+    Returns:
+      List of tuples like: (inbound_layer, node_index, tensor_index, tensor).
+    """
+    inputs_inbound = list(
+        zip(
+            nest.flatten(self.inbound_layers),
+            nest.flatten(self.node_indices),
+            nest.flatten(self.tensor_indices),
+            nest.flatten(self.input_tensors)))
+
+    if include_arguments:
+      keras_tensor_arguments = [
+          kt for kt in nest.flatten(self.arguments)
+          if hasattr(kt, '_keras_history')
+      ]
+
+      def _get_inbound(keras_tensor):
+        kh = keras_tensor._keras_history
+        return kh.layer, kh.node_index, kh.tensor_index, keras_tensor
+
+      arguments_inbound = nest.map_structure(_get_inbound,
+                                             keras_tensor_arguments)
+
+      return inputs_inbound + arguments_inbound
+    else:
+      return inputs_inbound
+
+  def _get_all_node_dependencies(self):
+    """Returns all of the nodes this node immediately depends on."""
+    node_deps = []
+    for layer, node_index, _, _ in self.iterate_inbound():
+      node_deps.append(layer._inbound_nodes[node_index])
+
+    for arg in nest.flatten(self.arguments):
+      if isinstance(arg, ops.Tensor) and hasattr(arg, '_keras_history'):
+        kh = arg._keras_history
+        node_deps.append(kh.layer._inbound_nodes[kh.node_index])
+
+    return node_deps
+
+  def get_config(self):
+    inbound_names = nest.map_structure(
+        lambda layer: layer.name if layer else None, self.inbound_layers)
+    return {
+        'outbound_layer': self.outbound_layer.name,
+        'inbound_layers': inbound_names,
+        'node_indices': self.node_indices,
+        'tensor_indices': self.tensor_indices
+    }