diff --git a/src/consensus/params.h b/src/consensus/params.h
index 6f4c6387f2a5..8f5e1040314f 100644
--- a/src/consensus/params.h
+++ b/src/consensus/params.h
@@ -43,8 +43,6 @@ struct Params {
     uint256 BIP34Hash;
     /** Block height at which BIP65 becomes active */
     int BIP65Height;
-    /** Block height at which BIP66 becomes active */
-    int BIP66Height;
     /**
      * Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,
      * (nPowTargetTimespan / nPowTargetSpacing) which is also used for BIP9 deployments.
diff --git a/src/policy/policy.h b/src/policy/policy.h
index 9b1323ac26f3..f6cc8888f481 100644
--- a/src/policy/policy.h
+++ b/src/policy/policy.h
@@ -52,7 +52,6 @@ static const unsigned int DUST_RELAY_TX_FEE = 1000;
  * blocks and we must accept those blocks.
  */
 static const unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VERIFY_FLAGS |
-                                                         SCRIPT_VERIFY_DERSIG |
                                                          SCRIPT_VERIFY_STRICTENC |
                                                          SCRIPT_VERIFY_MINIMALDATA |
                                                          SCRIPT_VERIFY_NULLDUMMY |
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index d3f1728890ca..0a3517117cbc 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -970,9 +970,6 @@ static UniValue SoftForkMajorityDesc(int version, CBlockIndex* pindex, const Con
         case 2:
             activated = pindex->nHeight >= consensusParams.BIP34Height;
             break;
-        case 3:
-            activated = pindex->nHeight >= consensusParams.BIP66Height;
-            break;
         case 4:
             activated = pindex->nHeight >= consensusParams.BIP65Height;
             break;
diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp
index f9b783588283..e65f6c4e4ddc 100644
--- a/src/script/interpreter.cpp
+++ b/src/script/interpreter.cpp
@@ -200,13 +200,8 @@ bool CheckSignatureEncoding(const vector<unsigned char> &vchSig, unsigned int fl
     if (vchSig.size() == 0) {
         return true;
     }
-    if ((flags & (SCRIPT_VERIFY_DERSIG | SCRIPT_VERIFY_LOW_S | SCRIPT_VERIFY_STRICTENC)) != 0 && !IsValidSignatureEncoding(vchSig)) {
+    if ((flags) != 0 && !IsValidSignatureEncoding(vchSig)) {
         return set_error(serror, SCRIPT_ERR_SIG_DER);
-    } else if ((flags & SCRIPT_VERIFY_LOW_S) != 0 && !IsLowDERSignature(vchSig, serror)) {
-        // serror is set
-        return false;
-    } else if ((flags & SCRIPT_VERIFY_STRICTENC) != 0 && !IsDefinedHashtypeSignature(vchSig)) {
-        return set_error(serror, SCRIPT_ERR_SIG_HASHTYPE);
     }
     return true;
 }
diff --git a/src/validation.cpp b/src/validation.cpp
index cf8d284bc6fa..32c6fb6fd27e 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -1746,11 +1746,6 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin
 
     unsigned int flags = fStrictPayToScriptHash ? SCRIPT_VERIFY_P2SH : SCRIPT_VERIFY_NONE;
 
-    // Start enforcing the DERSIG (BIP66) rule
-    if (pindex->nHeight >= chainparams.GetConsensus().BIP66Height) {
-        flags |= SCRIPT_VERIFY_DERSIG;
-    }
-
     // Start enforcing CHECKLOCKTIMEVERIFY (BIP65) rule
     if (pindex->nHeight >= chainparams.GetConsensus().BIP65Height) {
         flags |= SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY;