diff --git a/src/validation.cpp b/src/validation.cpp
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -1729,8 +1729,6 @@
     }
 
     const uint32_t flags = GetBlockScriptFlags(config, pindex->pprev);
-    const bool fIsMagneticAnomalyEnabled =
-        IsMagneticAnomalyEnabled(config, pindex->pprev);
 
     int64_t nTime2 = GetTimeMicros();
     nTimeForks += nTime2 - nTime1;
@@ -1764,14 +1762,11 @@
             nSigOpsCount += GetSigOpCountWithoutP2SH(tx, flags);
         }
 
-        if (fIsMagneticAnomalyEnabled || tx.IsCoinBase()) {
-            // We do not need to throw when a transaction is duplicated. If they
-            // are in the same block, CheckBlock will catch it, and if they are
-            // in a different block, it'll register as a double spend or BIP30
-            // violation. In both cases, we get a more meaningful feedback out
-            // of it.
-            AddCoins(view, tx, pindex->nHeight, true);
-        }
+        // We do not need to throw when a transaction is duplicated. If they are
+        // in the same block, CheckBlock will catch it, and if they are in a
+        // different block, it'll register as a double spend or BIP30 violation.
+        // In both cases, we get a more meaningful feedback out of it.
+        AddCoins(view, tx, pindex->nHeight, true);
     }
 
     for (const auto &ptx : block.vtx) {
@@ -1833,10 +1828,6 @@
 
         blockundo.vtxundo.push_back(CTxUndo());
         SpendCoins(view, tx, blockundo.vtxundo.back(), pindex->nHeight);
-
-        if (!fIsMagneticAnomalyEnabled) {
-            AddCoins(view, tx, pindex->nHeight);
-        }
     }
 
     int64_t nTime3 = GetTimeMicros();
@@ -2204,14 +2195,8 @@
     // remove transactions that are replay protected from the mempool. There is
     // no easy way to do this so we'll just discard the whole mempool and then
     // add the transaction of the block we just disconnected back.
-    //
-    // If we are deactivating Magnetic anomaly, we want to make sure we do not
-    // have transactions in the mempool that use newly introduced opcodes. As a
-    // result, we also cleanup the mempool.
-    if ((IsReplayProtectionEnabled(config, pindexDelete) &&
-         !IsReplayProtectionEnabled(config, pindexDelete->pprev)) ||
-        (IsMagneticAnomalyEnabled(config, pindexDelete) &&
-         !IsMagneticAnomalyEnabled(config, pindexDelete->pprev))) {
+    if (IsReplayProtectionEnabled(config, pindexDelete) &&
+        !IsReplayProtectionEnabled(config, pindexDelete->pprev)) {
         LogPrint(BCLog::MEMPOOL, "Clearing mempool for reorg");
 
         g_mempool.clear();
diff --git a/test/functional/abc-checkdatasig-activation.py b/test/functional/abc-checkdatasig-activation.py
--- a/test/functional/abc-checkdatasig-activation.py
+++ b/test/functional/abc-checkdatasig-activation.py
@@ -169,17 +169,6 @@
         add_tx(magneticanomalyblock, tx0)
         yield accepted(magneticanomalyblock)
 
-        self.log.info("Cause a reorg that deactivate the checkdatasig opcodes")
-
-        # Invalidate the checkdatasig block, ensure tx0 gets back to the mempool.
-        assert(tx0id not in set(node.getrawmempool()))
-
-        node.invalidateblock(format(magneticanomalyblock.sha256, 'x'))
-        assert(tx0id in set(node.getrawmempool()))
-
-        node.invalidateblock(format(fork_block.sha256, 'x'))
-        assert(tx0id not in set(node.getrawmempool()))
-
 
 if __name__ == '__main__':
     CheckDataSigActivationTest().main()
diff --git a/test/functional/abc-transaction-ordering.py b/test/functional/abc-transaction-ordering.py
--- a/test/functional/abc-transaction-ordering.py
+++ b/test/functional/abc-transaction-ordering.py
@@ -213,19 +213,6 @@
         assert_equal(node.getblockheader(node.getbestblockhash())['mediantime'],
                      MAGNETIC_ANOMALY_START_TIME - 1)
 
-        # Before we activate the Nov 15, 2018 HF, transaction order is respected.
-        def ordered_block(block_number, spend):
-            b = block(block_number, spend=spend, tx_count=16)
-            b.vtx = [b.vtx[0]] + sorted(b.vtx[1:], key=lambda tx: tx.get_id())
-            update_block(block_number)
-            return b
-
-        ordered_block(4444, out[16])
-        yield rejected(RejectResult(16, b'bad-txns-inputs-missingorspent'))
-
-        # Rewind bad block.
-        tip(5104)
-
         # Activate the Nov 15, 2018 HF
         block(5556, out[16], tx_count=16)
         yield accepted()
@@ -241,6 +228,13 @@
         # Rewind bad block.
         tip(5556)
 
+        # After we activate the Nov 15, 2018 HF, transaction order is enforced.
+        def ordered_block(block_number, spend):
+            b = block(block_number, spend=spend, tx_count=16)
+            b.vtx = [b.vtx[0]] + sorted(b.vtx[1:], key=lambda tx: tx.get_id())
+            update_block(block_number)
+            return b
+
         # Now that the fork activated, we need to order transaction per txid.
         ordered_block(4445, out[17])
         yield accepted()