diff --git a/orangecontrib/spectroscopy/preprocess/me_emsc.py b/orangecontrib/spectroscopy/preprocess/me_emsc.py
index 68a26d3cc..88b92997b 100644
--- a/orangecontrib/spectroscopy/preprocess/me_emsc.py
+++ b/orangecontrib/spectroscopy/preprocess/me_emsc.py
@@ -3,12 +3,13 @@
 from sklearn.decomposition import TruncatedSVD
 
 import Orange
+from Orange.data import Table
 from Orange.preprocess.preprocess import Preprocess
 from Orange.data.util import get_unique_names
 
 from orangecontrib.spectroscopy.data import getx
 from orangecontrib.spectroscopy.preprocess.utils import SelectColumn, CommonDomainOrderUnknowns, \
-    interpolate_extend_to
+    interpolate_extend_to, CommonDomainRef, table_eq_x
 from orangecontrib.spectroscopy.preprocess.emsc import weighted_wavenumbers, average_table_x
 
 
@@ -87,13 +88,13 @@ class ME_EMSCModel(SelectColumn):
     InheritEq = True
 
 
-class _ME_EMSC(CommonDomainOrderUnknowns):
+class _ME_EMSC(CommonDomainOrderUnknowns, CommonDomainRef):
 
     def __init__(self, reference, weights, ncomp, alpha0, gamma, maxNiter, fixedNiter, positiveRef, domain):
-        super().__init__(domain)
+        CommonDomainOrderUnknowns.__init__(self, domain)
+        CommonDomainRef.__init__(self, reference, domain)
         assert len(reference) == 1
-        self.reference = reference
-        self.weights = weights  # !!! THIS SHOULD BE A NP ARRAY (or similar) with inflection points
+        self.weights = weights
         self.ncomp = ncomp
         self.alpha0 = alpha0
         self.gamma = gamma
@@ -276,6 +277,24 @@ def iterate(spectra, correctedFirsIteration, residualsFirstIteration, wavenumber
         newspectra = np.hstack((newspectra, numberOfIterations.reshape(-1, 1),RMSEall.reshape(-1, 1)))
         return newspectra
 
+    def __eq__(self, other):
+        return CommonDomainRef.__eq__(self, other) \
+            and self.ncomp == other.ncomp \
+            and np.array_equal(self.alpha0, other.alpha0) \
+            and np.array_equal(self.gamma, other.gamma) \
+            and self.maxNiter == other.maxNiter \
+            and self.fixedNiter == other.fixedNiter \
+            and self.positiveRef == other.positiveRef \
+            and (self.weights == other.weights
+                 if not isinstance(self.weights, Table)
+                 else table_eq_x(self.weights, other.weights))
+
+    def __hash__(self):
+        weights = self.weights \
+            if not isinstance(self.weights, Table) else tuple(self.weights.X[0][:10])
+        return hash((CommonDomainRef.__hash__(self), weights, self.ncomp, tuple(self.alpha0),
+                     tuple(self.gamma), self.maxNiter, self.fixedNiter, self.positiveRef))
+
 
 class MissingReferenceException(Exception):
     pass
diff --git a/orangecontrib/spectroscopy/tests/test_me_emsc.py b/orangecontrib/spectroscopy/tests/test_me_emsc.py
index 8722d229d..b651d5a3e 100644
--- a/orangecontrib/spectroscopy/tests/test_me_emsc.py
+++ b/orangecontrib/spectroscopy/tests/test_me_emsc.py
@@ -208,6 +208,39 @@ def test_short_reference(self):
         # it was crashing before
         ME_EMSC(reference=reference)(self.spectra)
 
+    def test_eq(self):
+        ref = self.reference
+        spectra = self.spectra
+        d1 = ME_EMSC(reference=ref, ncomp=False, weights=False, max_iter=1)(spectra)
+        d2 = ME_EMSC(reference=ref, ncomp=False, weights=False, max_iter=1)(spectra)
+        self.assertEqual(d1.domain, d2.domain)
+        self.assertEqual(hash(d1.domain), hash(d2.domain))
+
+        d2 = ME_EMSC(reference=ref, ncomp=2, weights=False, max_iter=1)(spectra)
+        self.assertNotEqual(d1.domain, d2.domain)
+        self.assertNotEqual(hash(d1.domain), hash(d2.domain))
+
+        d2 = ME_EMSC(reference=ref, ncomp=False, weights=False, max_iter=1,
+                     n0=np.linspace(1.1, 1.4, 11),
+                     a=np.linspace(2, 7.1, 11))(spectra)
+        self.assertNotEqual(d1.domain, d2.domain)
+        self.assertNotEqual(hash(d1.domain), hash(d2.domain))
+
+        d2 = ME_EMSC(reference=ref, ncomp=False, weights=False, max_iter=2)(spectra)
+        self.assertNotEqual(d1.domain, d2.domain)
+        self.assertNotEqual(hash(d1.domain), hash(d2.domain))
+
+        r2 = ref.copy()
+        d2 = ME_EMSC(reference=r2, ncomp=False, weights=False, max_iter=1)(spectra)
+        self.assertEqual(d1.domain, d2.domain)
+        self.assertEqual(hash(d1.domain), hash(d2.domain))
+
+        with r2.unlocked():
+            r2[0][0] = 1
+        d2 = ME_EMSC(reference=r2, ncomp=False, weights=False, max_iter=1)(spectra)
+        self.assertNotEqual(d1.domain, d2.domain)
+        self.assertNotEqual(hash(d1.domain), hash(d2.domain))
+
 
 class TestInflectionPointWeighting(unittest.TestCase):