diff --git a/cardano-api/internal/Cardano/Api/Certificate.hs b/cardano-api/internal/Cardano/Api/Certificate.hs
index b4f442faa..cfc09a514 100644
--- a/cardano-api/internal/Cardano/Api/Certificate.hs
+++ b/cardano-api/internal/Cardano/Api/Certificate.hs
@@ -526,12 +526,10 @@ filterUnRegCreds =
         Ledger.GenesisDelegTxCert{} -> Nothing
     ConwayCertificate cEra conwayCert -> conwayEraOnwardsConstraints cEra $
       case conwayCert of
-        Ledger.RegTxCert _ -> Nothing
-        Ledger.UnRegTxCert cred -> Just cred
         Ledger.RegPoolTxCert _ -> Nothing
         Ledger.RetirePoolTxCert _ _ -> Nothing
         Ledger.RegDepositTxCert _ _ -> Nothing
-        Ledger.UnRegDepositTxCert _ _ -> Nothing
+        Ledger.UnRegDepositTxCert cred _ -> Just cred
         Ledger.DelegTxCert _ _ -> Nothing
         Ledger.RegDepositDelegTxCert{} -> Nothing
         Ledger.AuthCommitteeHotKeyTxCert{} -> Nothing
@@ -539,6 +537,10 @@ filterUnRegCreds =
         Ledger.RegDRepTxCert{} -> Nothing
         Ledger.UnRegDRepTxCert{} -> Nothing
         Ledger.UpdateDRepTxCert{} -> Nothing
+        -- those are old shelley patterns
+        Ledger.RegTxCert _ -> Nothing
+        -- stake cred deregistration w/o deposit
+        Ledger.UnRegTxCert cred -> Just cred
 
 filterUnRegDRepCreds
   :: Certificate era -> Maybe (Ledger.Credential Ledger.DRepRole Ledger.StandardCrypto)
@@ -546,8 +548,6 @@ filterUnRegDRepCreds = \case
   ShelleyRelatedCertificate _ _ -> Nothing
   ConwayCertificate cEra conwayCert -> conwayEraOnwardsConstraints cEra $
     case conwayCert of
-      Ledger.RegTxCert _ -> Nothing
-      Ledger.UnRegTxCert _ -> Nothing
       Ledger.RegPoolTxCert _ -> Nothing
       Ledger.RetirePoolTxCert _ _ -> Nothing
       Ledger.RegDepositTxCert _ _ -> Nothing
@@ -559,6 +559,10 @@ filterUnRegDRepCreds = \case
       Ledger.RegDRepTxCert{} -> Nothing
       Ledger.UnRegDRepTxCert cred _ -> Just cred
       Ledger.UpdateDRepTxCert{} -> Nothing
+      -- those are old shelley patterns
+      Ledger.RegTxCert _ -> Nothing
+      -- stake cred deregistration w/o deposit
+      Ledger.UnRegTxCert _ -> Nothing
 
 -- ----------------------------------------------------------------------------
 -- Internal conversion functions
diff --git a/cardano-api/internal/Cardano/Api/Genesis.hs b/cardano-api/internal/Cardano/Api/Genesis.hs
index 3b3e2038c..2b3a1325e 100644
--- a/cardano-api/internal/Cardano/Api/Genesis.hs
+++ b/cardano-api/internal/Cardano/Api/Genesis.hs
@@ -171,6 +171,7 @@ shelleyGenesisDefaults =
           -- pot = tx_fees + ρ * remaining_reserves
           & ppRhoL .~ unsafeBR (1 % 10) -- How much of reserves goes into pot
           & ppTauL .~ unsafeBR (1 % 10) -- τ * remaining_reserves is sent to treasury every epoch
+          & ppKeyDepositL .~ 400000 -- require a non-zero deposit when registering keys
     , -- genesis keys and initial funds
       sgGenDelegs = M.empty
     , sgStaking = emptyGenesisStaking