diff --git a/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/mappers.ts b/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/mappers.ts
index 6042d74ec33..d5b7b1cd980 100644
--- a/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/mappers.ts
+++ b/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/mappers.ts
@@ -67,11 +67,12 @@ export const toProtocolParams = ({
   governance_action_validity_period,
   governance_action_deposit,
   drep_deposit,
-  drep_inactivity_period
+  drep_inactivity_period,
+  min_fee_ref_script_cost_per_byte
 }: ProtocolParamsModel): Cardano.ProtocolParameters => ({
   coinsPerUtxoByte: Number(coins_per_utxo_size),
   collateralPercentage: collateral_percent,
-  committeeTermLimit: Number(committee_term_limit),
+  committeeTermLimit: Cardano.EpochNo(committee_term_limit),
   costModels: mapCostModels(costs),
   dRepDeposit: Number(drep_deposit),
   dRepInactivityPeriod: Cardano.EpochNo(drep_inactivity_period),
@@ -96,6 +97,7 @@ export const toProtocolParams = ({
   minCommitteeSize: Number(min_committee_size),
   minFeeCoefficient: min_fee_a,
   minFeeConstant: min_fee_b,
+  minFeeRefScriptCostPerByte: String(min_fee_ref_script_cost_per_byte),
   minPoolCost: Number(min_pool_cost),
   monetaryExpansion: String(monetary_expand_rate),
   poolDeposit: Number(pool_deposit),
diff --git a/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/types.ts b/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/types.ts
index 4cab44e7aed..f893e08bdd2 100644
--- a/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/types.ts
+++ b/packages/cardano-services/src/NetworkInfo/DbSyncNetworkInfoProvider/types.ts
@@ -42,6 +42,7 @@ export interface ProtocolParamsModel {
   max_bh_size: number;
   optimal_pool_count: number;
   influence: number;
+  min_fee_ref_script_cost_per_byte: number;
   monetary_expand_rate: number;
   treasury_growth_rate: number;
   decentralisation: number;
diff --git a/packages/core/src/Cardano/types/Governance.ts b/packages/core/src/Cardano/types/Governance.ts
index 268fae39655..92df6798c4b 100644
--- a/packages/core/src/Cardano/types/Governance.ts
+++ b/packages/core/src/Cardano/types/Governance.ts
@@ -2,7 +2,7 @@ import * as Crypto from '@cardano-sdk/crypto';
 import { Credential, CredentialType, RewardAccount } from '../Address';
 import { EpochNo, Fraction, ProtocolVersion, TransactionId } from '.';
 import { Lovelace } from './Value';
-import { ProtocolParametersUpdate } from './ProtocolParameters';
+import { ProtocolParametersUpdateConway } from './ProtocolParameters';
 
 export type Anchor = {
   url: string;
@@ -43,7 +43,7 @@ export type Constitution = {
 export type ParameterChangeAction = {
   __typename: GovernanceActionType.parameter_change_action;
   governanceActionId: GovernanceActionId | null;
-  protocolParamUpdate: ProtocolParametersUpdate;
+  protocolParamUpdate: ProtocolParametersUpdateConway;
   policyHash: Crypto.Hash28ByteBase16 | null;
 };
 
diff --git a/packages/core/src/Cardano/types/ProtocolParameters.ts b/packages/core/src/Cardano/types/ProtocolParameters.ts
index d1557a97821..a47a960a17c 100644
--- a/packages/core/src/Cardano/types/ProtocolParameters.ts
+++ b/packages/core/src/Cardano/types/ProtocolParameters.ts
@@ -110,11 +110,13 @@ type BabbageProtocolParameters = Omit<AlonzoProtocolParams, 'coinsPerUtxoWord' |
 export interface PoolVotingThresholds {
   motionNoConfidence: Fraction;
   committeeNormal: Fraction;
-  commiteeNoConfidence: Fraction;
+  committeeNoConfidence: Fraction;
   hardForkInitiation: Fraction;
+  securityRelevantParamVotingThreshold: Fraction;
 }
 
-export interface DelegateRepresentativeThresholds extends PoolVotingThresholds {
+export interface DelegateRepresentativeThresholds
+  extends Omit<PoolVotingThresholds, 'securityRelevantParamVotingThreshold'> {
   updateConstitution: Fraction;
   ppNetworkGroup: Fraction;
   ppEconomicGroup: Fraction;
@@ -127,20 +129,21 @@ type NewProtocolParamsInConway = {
   poolVotingThresholds: PoolVotingThresholds;
   dRepVotingThresholds: DelegateRepresentativeThresholds;
   minCommitteeSize: number;
-  committeeTermLimit: number;
+  committeeTermLimit: EpochNo;
   governanceActionValidityPeriod: EpochNo;
   governanceActionDeposit: number;
   dRepDeposit: number;
   dRepInactivityPeriod: EpochNo;
+  minFeeRefScriptCostPerByte: string;
 };
 
-type ConwayProtocolParameters = BabbageProtocolParameters & NewProtocolParamsInConway;
+export type ProtocolParameters = BabbageProtocolParameters & NewProtocolParamsInConway;
+export type ConwayProtocolParameters = Omit<ProtocolParameters, 'protocolVersion'>;
 
-export type ProtocolParameters = ConwayProtocolParameters;
-
-// Even tho extraEntropy was deprecated on babbage era, it is still present in the ProtocolParametersUpdate structure
-// since this structure is backward compatible with all eras.
+// Even tho extraEntropy was deprecated on babbage era, and protocolVersion was deprecated in conway era,
+// they are still present in the ProtocolParametersUpdate structure since this structure is backward compatible with all eras.
 export type ProtocolParametersUpdate = Partial<ProtocolParameters & Pick<AlonzoProtocolParams, 'extraEntropy'>>;
+export type ProtocolParametersUpdateConway = Partial<ConwayProtocolParameters>;
 
 export type GenesisDelegateKeyHash = Crypto.Hash28ByteBase16;
 export type ProposedProtocolParameterUpdates = Map<GenesisDelegateKeyHash, ProtocolParametersUpdate>;
diff --git a/packages/core/src/Serialization/Update/DrepVotingThresholds.ts b/packages/core/src/Serialization/Update/DrepVotingThresholds.ts
index 713ca933ea6..aebba9b9390 100644
--- a/packages/core/src/Serialization/Update/DrepVotingThresholds.ts
+++ b/packages/core/src/Serialization/Update/DrepVotingThresholds.ts
@@ -168,7 +168,7 @@ export class DrepVotingThresholds {
    */
   toCore(): Cardano.DelegateRepresentativeThresholds {
     return {
-      commiteeNoConfidence: this.#committeeNoConfidence.toCore(),
+      committeeNoConfidence: this.#committeeNoConfidence.toCore(),
       committeeNormal: this.#committeeNormal.toCore(),
       hardForkInitiation: this.#hardForkInitiation.toCore(),
       motionNoConfidence: this.#motionNoConfidence.toCore(),
@@ -190,7 +190,7 @@ export class DrepVotingThresholds {
     return new DrepVotingThresholds(
       UnitInterval.fromCore(core.motionNoConfidence),
       UnitInterval.fromCore(core.committeeNormal),
-      UnitInterval.fromCore(core.commiteeNoConfidence),
+      UnitInterval.fromCore(core.committeeNoConfidence),
       UnitInterval.fromCore(core.updateConstitution),
       UnitInterval.fromCore(core.hardForkInitiation),
       UnitInterval.fromCore(core.ppNetworkGroup),
diff --git a/packages/core/src/Serialization/Update/PoolVotingThresholds.ts b/packages/core/src/Serialization/Update/PoolVotingThresholds.ts
index ba2c08ec3f2..ee7ed392240 100644
--- a/packages/core/src/Serialization/Update/PoolVotingThresholds.ts
+++ b/packages/core/src/Serialization/Update/PoolVotingThresholds.ts
@@ -3,7 +3,7 @@ import { CborReader, CborWriter } from '../CBOR';
 import { HexBlob, InvalidArgumentError } from '@cardano-sdk/util';
 import { UnitInterval } from '../Common';
 
-const POOL_VOTING_THRESHOLDS_SIZE = 4;
+const POOL_VOTING_THRESHOLDS_SIZE = 5;
 
 /**
  * Governance actions are ratified through on-chain voting. Different
@@ -17,6 +17,7 @@ export class PoolVotingThresholds {
   #committeeNormal: UnitInterval;
   #committeeNoConfidence: UnitInterval;
   #hardForkInitiation: UnitInterval;
+  #securityRelevantParamVotingThreshold: UnitInterval;
   #originalBytes: HexBlob | undefined = undefined;
 
   /**
@@ -35,12 +36,14 @@ export class PoolVotingThresholds {
     motionNoConfidence: UnitInterval,
     committeeNormal: UnitInterval,
     committeeNoConfidence: UnitInterval,
-    hardForkInitiation: UnitInterval
+    hardForkInitiation: UnitInterval,
+    securityRelevantParamVotingThreshold: UnitInterval
   ) {
     this.#motionNoConfidence = motionNoConfidence;
     this.#committeeNormal = committeeNormal;
     this.#committeeNoConfidence = committeeNoConfidence;
     this.#hardForkInitiation = hardForkInitiation;
+    this.#securityRelevantParamVotingThreshold = securityRelevantParamVotingThreshold;
   }
 
   /**
@@ -59,6 +62,7 @@ export class PoolVotingThresholds {
     //   , unit_interval ; committee normal
     //   , unit_interval ; committee no confidence
     //   , unit_interval ; hard fork initiation
+    //   , unit_interval ; security relevant parameter voting threshold
     //   ]
     writer.writeStartArray(POOL_VOTING_THRESHOLDS_SIZE);
 
@@ -66,6 +70,7 @@ export class PoolVotingThresholds {
     writer.writeEncodedValue(Buffer.from(this.#committeeNormal.toCbor(), 'hex'));
     writer.writeEncodedValue(Buffer.from(this.#committeeNoConfidence.toCbor(), 'hex'));
     writer.writeEncodedValue(Buffer.from(this.#hardForkInitiation.toCbor(), 'hex'));
+    writer.writeEncodedValue(Buffer.from(this.#securityRelevantParamVotingThreshold.toCbor(), 'hex'));
 
     return writer.encodeAsHex();
   }
@@ -91,6 +96,7 @@ export class PoolVotingThresholds {
     const committeeNormal = UnitInterval.fromCbor(HexBlob.fromBytes(reader.readEncodedValue()));
     const committeeNoConfidence = UnitInterval.fromCbor(HexBlob.fromBytes(reader.readEncodedValue()));
     const hardForkInitiation = UnitInterval.fromCbor(HexBlob.fromBytes(reader.readEncodedValue()));
+    const securityRelevantParamVotingThreshold = UnitInterval.fromCbor(HexBlob.fromBytes(reader.readEncodedValue()));
 
     reader.readEndArray();
 
@@ -98,7 +104,8 @@ export class PoolVotingThresholds {
       motionNoConfidence,
       committeeNormal,
       committeeNoConfidence,
-      hardForkInitiation
+      hardForkInitiation,
+      securityRelevantParamVotingThreshold
     );
 
     thresholds.#originalBytes = cbor;
@@ -107,16 +114,17 @@ export class PoolVotingThresholds {
   }
 
   /**
-   * Creates a Core PoolVotingThresholdsSHOLDS_SIZE object from the current PoolVotingThresholds object.
+   * Creates a Core PoolVotingThresholds object from the current PoolVotingThresholds object.
    *
    * @returns The Core Prices object.
    */
   toCore(): Cardano.PoolVotingThresholds {
     return {
-      commiteeNoConfidence: this.#committeeNoConfidence.toCore(),
+      committeeNoConfidence: this.#committeeNoConfidence.toCore(),
       committeeNormal: this.#committeeNormal.toCore(),
       hardForkInitiation: this.#hardForkInitiation.toCore(),
-      motionNoConfidence: this.#motionNoConfidence.toCore()
+      motionNoConfidence: this.#motionNoConfidence.toCore(),
+      securityRelevantParamVotingThreshold: this.#securityRelevantParamVotingThreshold.toCore()
     };
   }
 
@@ -129,8 +137,9 @@ export class PoolVotingThresholds {
     return new PoolVotingThresholds(
       UnitInterval.fromCore(core.motionNoConfidence),
       UnitInterval.fromCore(core.committeeNormal),
-      UnitInterval.fromCore(core.commiteeNoConfidence),
-      UnitInterval.fromCore(core.hardForkInitiation)
+      UnitInterval.fromCore(core.committeeNoConfidence),
+      UnitInterval.fromCore(core.hardForkInitiation),
+      UnitInterval.fromCore(core.securityRelevantParamVotingThreshold)
     );
   }
 
@@ -223,4 +232,13 @@ export class PoolVotingThresholds {
   hardForkInitiation(): UnitInterval {
     return this.#hardForkInitiation;
   }
+
+  /**
+   * Gets the security relevant parameter voting threshold
+   *
+   * @returns security relevant parameter voting threshold.
+   */
+  securityRelevantParamVotingThreshold(): UnitInterval {
+    return this.#securityRelevantParamVotingThreshold;
+  }
 }
diff --git a/packages/core/src/Serialization/Update/ProtocolParamUpdate.ts b/packages/core/src/Serialization/Update/ProtocolParamUpdate.ts
index 17c26f3d93e..169258bd675 100644
--- a/packages/core/src/Serialization/Update/ProtocolParamUpdate.ts
+++ b/packages/core/src/Serialization/Update/ProtocolParamUpdate.ts
@@ -46,6 +46,7 @@ export class ProtocolParamUpdate {
   #governanceActionDeposit: number | undefined;
   #drepDeposit: number | undefined;
   #drepInactivityPeriod: number | undefined;
+  #minFeeRefScriptCostPerByte: UnitInterval | undefined;
   #originalBytes: HexBlob | undefined = undefined;
 
   /**
@@ -90,6 +91,7 @@ export class ProtocolParamUpdate {
     //   , ? 30: coin                   ; governance action deposit
     //   , ? 31: coin                   ; DRep deposit
     //   , ? 32: epoch                  ; DRep inactivity period
+    //   , ? 33: nonnegative_interval   ; MinFee RefScriptCostPerByte
     //   }
     writer.writeStartMap(this.#getMapSize());
 
@@ -254,6 +256,12 @@ export class ProtocolParamUpdate {
       writer.writeInt(32n);
       writer.writeInt(this.#drepInactivityPeriod);
     }
+
+    if (this.#minFeeRefScriptCostPerByte) {
+      writer.writeInt(33n);
+      writer.writeEncodedValue(Buffer.from(this.#minFeeRefScriptCostPerByte.toCbor(), 'hex'));
+    }
+
     return writer.encodeAsHex();
   }
 
@@ -373,6 +381,9 @@ export class ProtocolParamUpdate {
         case 32n:
           params.#drepInactivityPeriod = Number(reader.readInt());
           break;
+        case 33n:
+          params.#minFeeRefScriptCostPerByte = UnitInterval.fromCbor(HexBlob.fromBytes(reader.readEncodedValue()));
+          break;
       }
     }
 
@@ -392,7 +403,7 @@ export class ProtocolParamUpdate {
     return {
       coinsPerUtxoByte: this.#adaPerUtxoByte ? Number(this.#adaPerUtxoByte) : undefined,
       collateralPercentage: this.#collateralPercentage,
-      committeeTermLimit: this.#committeeTermLimit,
+      committeeTermLimit: this.#committeeTermLimit ? Cardano.EpochNo(this.#committeeTermLimit) : undefined,
       costModels: this.#costModels?.toCore(),
       dRepDeposit: this.#drepDeposit,
       dRepInactivityPeriod: this.#drepInactivityPeriod ? Cardano.EpochNo(this.#drepInactivityPeriod) : undefined,
@@ -414,6 +425,9 @@ export class ProtocolParamUpdate {
       minCommitteeSize: this.#minCommitteeSize,
       minFeeCoefficient: this.#minFeeA ? Number(this.#minFeeA) : undefined,
       minFeeConstant: this.#minFeeB ? Number(this.#minFeeB) : undefined,
+      minFeeRefScriptCostPerByte: this.#minFeeRefScriptCostPerByte
+        ? this.#minFeeRefScriptCostPerByte.toFloat().toString()
+        : undefined,
       minPoolCost: this.#minPoolCost ? Number(this.#minPoolCost) : undefined,
       monetaryExpansion: this.#expansionRate ? this.#expansionRate.toFloat().toString() : undefined,
       poolDeposit: this.#poolDeposit ? Number(this.#poolDeposit) : undefined,
@@ -432,7 +446,9 @@ export class ProtocolParamUpdate {
    *
    * @param parametersUpdate core parametersUpdate object.
    */
-  static fromCore(parametersUpdate: Cardano.ProtocolParametersUpdate) {
+  static fromCore<T extends Cardano.ProtocolParametersUpdateConway = Cardano.ProtocolParametersUpdate>(
+    parametersUpdate: T
+  ) {
     const params = new ProtocolParamUpdate();
 
     params.#minFeeA = parametersUpdate.minFeeCoefficient ? BigInt(parametersUpdate.minFeeCoefficient) : undefined;
@@ -456,14 +472,10 @@ export class ProtocolParamUpdate {
       ? UnitInterval.fromFloat(Number(parametersUpdate.decentralizationParameter))
       : undefined;
     params.#minPoolCost = parametersUpdate.minPoolCost ? BigInt(parametersUpdate.minPoolCost) : undefined;
-    params.#protocolVersion = parametersUpdate.protocolVersion
-      ? ProtocolVersion.fromCore(parametersUpdate.protocolVersion)
-      : undefined;
     params.#maxValueSize = parametersUpdate.maxValueSize;
     params.#maxTxSize = parametersUpdate.maxTxSize;
     params.#collateralPercentage = parametersUpdate.collateralPercentage;
     params.#maxCollateralInputs = parametersUpdate.maxCollateralInputs;
-    params.#extraEntropy = parametersUpdate.extraEntropy ? HexBlob(parametersUpdate.extraEntropy) : undefined;
     params.#costModels = parametersUpdate.costModels ? Costmdls.fromCore(parametersUpdate.costModels) : undefined;
     params.#executionCosts = parametersUpdate.prices ? ExUnitPrices.fromCore(parametersUpdate.prices) : undefined;
     params.#maxTxExUnits = parametersUpdate.maxExecutionUnitsPerTransaction
@@ -485,6 +497,15 @@ export class ProtocolParamUpdate {
     params.#governanceActionDeposit = parametersUpdate.governanceActionDeposit;
     params.#drepDeposit = parametersUpdate.dRepDeposit;
     params.#drepInactivityPeriod = parametersUpdate.dRepInactivityPeriod;
+    params.#minFeeRefScriptCostPerByte = parametersUpdate.minFeeRefScriptCostPerByte
+      ? UnitInterval.fromFloat(Number(parametersUpdate.minFeeRefScriptCostPerByte))
+      : undefined;
+
+    const { protocolVersion, extraEntropy } = parametersUpdate as unknown as Cardano.ProtocolParametersUpdate;
+    if (protocolVersion !== undefined || extraEntropy !== undefined) {
+      params.#protocolVersion = protocolVersion ? ProtocolVersion.fromCore(protocolVersion) : undefined;
+      params.#extraEntropy = extraEntropy ? HexBlob(extraEntropy) : undefined;
+    }
 
     return params;
   }
@@ -1177,6 +1198,10 @@ export class ProtocolParamUpdate {
     return this.#drepInactivityPeriod;
   }
 
+  minFeeRefScriptCostPerByte(): UnitInterval | undefined {
+    return this.#minFeeRefScriptCostPerByte;
+  }
+
   /**
    * Gets the size of the serialized map.
    *
@@ -1217,6 +1242,7 @@ export class ProtocolParamUpdate {
     if (this.#governanceActionDeposit !== undefined) ++mapSize;
     if (this.#drepDeposit !== undefined) ++mapSize;
     if (this.#drepInactivityPeriod !== undefined) ++mapSize;
+    if (this.#minFeeRefScriptCostPerByte !== undefined) ++mapSize;
 
     return mapSize;
   }
diff --git a/packages/core/test/Serialization/TransactionBody/ProposalProcedure/ParameterChangeAction.test.ts b/packages/core/test/Serialization/TransactionBody/ProposalProcedure/ParameterChangeAction.test.ts
index 0124495e229..56c056ca747 100644
--- a/packages/core/test/Serialization/TransactionBody/ProposalProcedure/ParameterChangeAction.test.ts
+++ b/packages/core/test/Serialization/TransactionBody/ProposalProcedure/ParameterChangeAction.test.ts
@@ -7,7 +7,7 @@ import { ParameterChangeAction } from '../../../../src/Serialization';
 
 // Test data used in the following tests was generated with the cardano-serialization-lib
 const cbor = HexBlob(
-  '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'
+  '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'
 );
 
 const vasilPlutusV1Costmdls = [
@@ -36,12 +36,15 @@ const vasilPlutusV2Costmdls = [
 
 const core = {
   __typename: Cardano.GovernanceActionType.parameter_change_action,
-  governanceActionId: { actionIndex: 3, id: '0000000000000000000000000000000000000000000000000000000000000000' },
+  governanceActionId: {
+    actionIndex: 3,
+    id: Cardano.TransactionId('0000000000000000000000000000000000000000000000000000000000000000')
+  },
   policyHash: Hash28ByteBase16('8293d319ef5b3ac72366dd28006bd315b715f7e7cfcbd3004129b80d'),
   protocolParamUpdate: {
     coinsPerUtxoByte: 35_000,
     collateralPercentage: 852,
-    committeeTermLimit: 200,
+    committeeTermLimit: Cardano.EpochNo(200),
     costModels: new Map([
       [PlutusLanguageVersion.V1, vasilPlutusV1Costmdls],
       [PlutusLanguageVersion.V2, vasilPlutusV2Costmdls]
@@ -49,7 +52,7 @@ const core = {
     dRepDeposit: 2000,
     dRepInactivityPeriod: EpochNo(5000),
     dRepVotingThresholds: {
-      commiteeNoConfidence: { denominator: 2, numerator: 2 },
+      committeeNoConfidence: { denominator: 2, numerator: 2 },
       committeeNormal: { denominator: 1, numerator: 1 },
       hardForkInitiation: { denominator: 4, numerator: 4 },
       motionNoConfidence: { denominator: 0, numerator: 0 },
@@ -81,13 +84,13 @@ const core = {
     poolInfluence: '0.5',
     poolRetirementEpochBound: 800,
     poolVotingThresholds: {
-      commiteeNoConfidence: { denominator: 2, numerator: 2 },
+      committeeNoConfidence: { denominator: 2, numerator: 2 },
       committeeNormal: { denominator: 1, numerator: 1 },
       hardForkInitiation: { denominator: 3, numerator: 3 },
-      motionNoConfidence: { denominator: 0, numerator: 0 }
+      motionNoConfidence: { denominator: 0, numerator: 0 },
+      securityRelevantParamVotingThreshold: { denominator: 1, numerator: 1 }
     },
     prices: { memory: 0.5, steps: 0.5 },
-    protocolVersion: { major: 1, minor: 3 },
     stakeKeyDeposit: 2_000_000,
     treasuryExpansion: '0.25'
   }
diff --git a/packages/core/test/Serialization/Update/DrepVotingThresholds.test.ts b/packages/core/test/Serialization/Update/DrepVotingThresholds.test.ts
index d6037b5a5fa..c3909516d9a 100644
--- a/packages/core/test/Serialization/Update/DrepVotingThresholds.test.ts
+++ b/packages/core/test/Serialization/Update/DrepVotingThresholds.test.ts
@@ -9,7 +9,7 @@ const cbor = HexBlob(
 );
 
 const core = {
-  commiteeNoConfidence: { denominator: 2, numerator: 2 },
+  committeeNoConfidence: { denominator: 2, numerator: 2 },
   committeeNormal: { denominator: 1, numerator: 1 },
   hardForkInitiation: { denominator: 4, numerator: 4 },
   motionNoConfidence: { denominator: 0, numerator: 0 },
@@ -25,7 +25,7 @@ describe('DrepVotingThresholds', () => {
   it('can decode DrepVotingThresholds from CBOR', () => {
     const thresholds = DrepVotingThresholds.fromCbor(cbor);
 
-    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.commiteeNoConfidence);
+    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.committeeNoConfidence);
     expect(thresholds.committeeNormal().toCore()).toEqual(core.committeeNormal);
     expect(thresholds.hardForkInitiation().toCore()).toEqual(core.hardForkInitiation);
     expect(thresholds.motionNoConfidence().toCore()).toEqual(core.motionNoConfidence);
@@ -40,7 +40,7 @@ describe('DrepVotingThresholds', () => {
   it('can decode DrepVotingThresholds from Core', () => {
     const thresholds = DrepVotingThresholds.fromCore(core);
 
-    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.commiteeNoConfidence);
+    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.committeeNoConfidence);
     expect(thresholds.committeeNormal().toCore()).toEqual(core.committeeNormal);
     expect(thresholds.hardForkInitiation().toCore()).toEqual(core.hardForkInitiation);
     expect(thresholds.motionNoConfidence().toCore()).toEqual(core.motionNoConfidence);
diff --git a/packages/core/test/Serialization/Update/PoolVotingThresholds.test.ts b/packages/core/test/Serialization/Update/PoolVotingThresholds.test.ts
index d0d15859dec..c9236c8c766 100644
--- a/packages/core/test/Serialization/Update/PoolVotingThresholds.test.ts
+++ b/packages/core/test/Serialization/Update/PoolVotingThresholds.test.ts
@@ -1,35 +1,43 @@
 /* eslint-disable sonarjs/no-duplicate-string */
+import { Cardano } from '../../../src';
 import { HexBlob } from '@cardano-sdk/util';
 import { PoolVotingThresholds } from '../../../src/Serialization';
 
 // Test data used in the following tests was generated with the cardano-serialization-lib
 
-const cbor = HexBlob('84d81e820000d81e820101d81e820202d81e820303');
+const cbor = HexBlob('85d81e820000d81e820101d81e820202d81e820303d81e820101');
 
-const core = {
-  commiteeNoConfidence: { denominator: 2, numerator: 2 },
+const core: Cardano.PoolVotingThresholds = {
+  committeeNoConfidence: { denominator: 2, numerator: 2 },
   committeeNormal: { denominator: 1, numerator: 1 },
   hardForkInitiation: { denominator: 3, numerator: 3 },
-  motionNoConfidence: { denominator: 0, numerator: 0 }
+  motionNoConfidence: { denominator: 0, numerator: 0 },
+  securityRelevantParamVotingThreshold: { denominator: 1, numerator: 1 }
 };
 
 describe('PoolVotingThresholds', () => {
   it('can decode PoolVotingThresholds from CBOR', () => {
     const thresholds = PoolVotingThresholds.fromCbor(cbor);
 
-    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.commiteeNoConfidence);
+    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.committeeNoConfidence);
     expect(thresholds.committeeNormal().toCore()).toEqual(core.committeeNormal);
     expect(thresholds.hardForkInitiation().toCore()).toEqual(core.hardForkInitiation);
     expect(thresholds.motionNoConfidence().toCore()).toEqual(core.motionNoConfidence);
+    expect(thresholds.securityRelevantParamVotingThreshold().toCore()).toEqual(
+      core.securityRelevantParamVotingThreshold
+    );
   });
 
   it('can decode PoolVotingThresholds from Core', () => {
     const thresholds = PoolVotingThresholds.fromCore(core);
 
-    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.commiteeNoConfidence);
+    expect(thresholds.committeeNoConfidence().toCore()).toEqual(core.committeeNoConfidence);
     expect(thresholds.committeeNormal().toCore()).toEqual(core.committeeNormal);
     expect(thresholds.hardForkInitiation().toCore()).toEqual(core.hardForkInitiation);
     expect(thresholds.motionNoConfidence().toCore()).toEqual(core.motionNoConfidence);
+    expect(thresholds.securityRelevantParamVotingThreshold().toCore()).toEqual(
+      core.securityRelevantParamVotingThreshold
+    );
   });
 
   it('can encode PoolVotingThresholds to CBOR', () => {
diff --git a/packages/core/test/Serialization/Update/ProtocolParamUpdate.test.ts b/packages/core/test/Serialization/Update/ProtocolParamUpdate.test.ts
index 1df145fcc58..b5a6e37bb69 100644
--- a/packages/core/test/Serialization/Update/ProtocolParamUpdate.test.ts
+++ b/packages/core/test/Serialization/Update/ProtocolParamUpdate.test.ts
@@ -1,4 +1,5 @@
 /* eslint-disable sonarjs/no-duplicate-string */
+import { Cardano } from '../../../src';
 import { EpochNo, PlutusLanguageVersion } from '../../../src/Cardano';
 import { HexBlob } from '@cardano-sdk/util';
 import { ProtocolParamUpdate } from '../../../src/Serialization/Update/ProtocolParamUpdate';
@@ -34,7 +35,7 @@ const cbor = HexBlob(
 );
 
 const conwayCbor = HexBlob(
-  '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'
+  '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'
 );
 
 const core = {
@@ -67,10 +68,10 @@ const core = {
   treasuryExpansion: '0.25'
 };
 
-const conwayCore = {
+const conwayCore: Cardano.ProtocolParametersUpdate = {
   coinsPerUtxoByte: 35_000,
   collateralPercentage: 852,
-  committeeTermLimit: 200,
+  committeeTermLimit: EpochNo(200),
   costModels: new Map([
     [PlutusLanguageVersion.V1, vasilPlutusV1Costmdls],
     [PlutusLanguageVersion.V2, vasilPlutusV2Costmdls]
@@ -78,7 +79,7 @@ const conwayCore = {
   dRepDeposit: 2000,
   dRepInactivityPeriod: EpochNo(5000),
   dRepVotingThresholds: {
-    commiteeNoConfidence: { denominator: 2, numerator: 2 },
+    committeeNoConfidence: { denominator: 2, numerator: 2 },
     committeeNormal: { denominator: 1, numerator: 1 },
     hardForkInitiation: { denominator: 4, numerator: 4 },
     motionNoConfidence: { denominator: 0, numerator: 0 },
@@ -104,16 +105,18 @@ const conwayCore = {
   minCommitteeSize: 100,
   minFeeCoefficient: 100,
   minFeeConstant: 200,
+  minFeeRefScriptCostPerByte: '44.5',
   minPoolCost: 1000,
   monetaryExpansion: '0.3333333333333333',
   poolDeposit: 200_000_000,
   poolInfluence: '0.5',
   poolRetirementEpochBound: 800,
   poolVotingThresholds: {
-    commiteeNoConfidence: { denominator: 2, numerator: 2 },
+    committeeNoConfidence: { denominator: 2, numerator: 2 },
     committeeNormal: { denominator: 1, numerator: 1 },
     hardForkInitiation: { denominator: 3, numerator: 3 },
-    motionNoConfidence: { denominator: 0, numerator: 0 }
+    motionNoConfidence: { denominator: 0, numerator: 0 },
+    securityRelevantParamVotingThreshold: { denominator: 1, numerator: 1 }
   },
   prices: { memory: 0.5, steps: 0.5 },
   protocolVersion: { major: 1, minor: 3 },
@@ -211,7 +214,7 @@ describe('ProtocolParamUpdate', () => {
     expect(proposedParams.drepDeposit()).toEqual(2000);
     expect(proposedParams.drepInactivityPeriod()).toEqual(5000);
     expect(proposedParams.drepVotingThresholds()?.toCore()).toEqual({
-      commiteeNoConfidence: { denominator: 2, numerator: 2 },
+      committeeNoConfidence: { denominator: 2, numerator: 2 },
       committeeNormal: { denominator: 1, numerator: 1 },
       hardForkInitiation: { denominator: 4, numerator: 4 },
       motionNoConfidence: { denominator: 0, numerator: 0 },
@@ -223,11 +226,13 @@ describe('ProtocolParamUpdate', () => {
       updateConstitution: { denominator: 3, numerator: 3 }
     });
     expect(proposedParams.poolVotingThresholds()?.toCore()).toEqual({
-      commiteeNoConfidence: { denominator: 2, numerator: 2 },
+      committeeNoConfidence: { denominator: 2, numerator: 2 },
       committeeNormal: { denominator: 1, numerator: 1 },
       hardForkInitiation: { denominator: 3, numerator: 3 },
-      motionNoConfidence: { denominator: 0, numerator: 0 }
+      motionNoConfidence: { denominator: 0, numerator: 0 },
+      securityRelevantParamVotingThreshold: { denominator: 1, numerator: 1 }
     });
+    expect(proposedParams.minFeeRefScriptCostPerByte()?.toFloat()).toEqual(44.5);
   });
 
   // eslint-disable-next-line max-statements
diff --git a/packages/util-dev/src/mockProviders/mockData.ts b/packages/util-dev/src/mockProviders/mockData.ts
index b655b625052..5a6d7a703b2 100644
--- a/packages/util-dev/src/mockProviders/mockData.ts
+++ b/packages/util-dev/src/mockProviders/mockData.ts
@@ -42,7 +42,7 @@ export const protocolParameters = {
   prices: { memory: 0.0577, steps: 0.000_007_21 },
   protocolVersion: { major: 5, minor: 0 },
   stakeKeyDeposit: 2_000_000
-} as Cardano.ProtocolParameters;
+} as Required<Cardano.ProtocolParametersUpdate>;
 
 export const epochRewards = [
   {