diff --git a/sdks/js/packages/spark-sdk/src/services/leaf-manager.ts b/sdks/js/packages/spark-sdk/src/services/leaf-manager.ts
index d6dd4970b..def2436cb 100644
--- a/sdks/js/packages/spark-sdk/src/services/leaf-manager.ts
+++ b/sdks/js/packages/spark-sdk/src/services/leaf-manager.ts
@@ -1554,7 +1554,12 @@ export default class LeafManager {
           }
           nodeIds.push(node.id);
         } else {
-          validNodes.push(node);
+          if (doesTxnNeedRenewed(nodeSequence)) {
+            nodesToRenewNodeTxn.push(node);
+            nodeIds.push(node.id);
+          } else {
+            validNodes.push(node);
+          }
         }
       } catch (err) {
         // Skip this node — don't let one malformed leaf abort the entire batch.
diff --git a/spark/so/chain/watch_chain.go b/spark/so/chain/watch_chain.go
index 5ae696e05..d48901418 100644
--- a/spark/so/chain/watch_chain.go
+++ b/spark/so/chain/watch_chain.go
@@ -820,7 +820,24 @@ func handleBlock(
 	}
 
 	logger.Sugar().Infof("Started processing coop exits at block height %d", blockHeight)
-	// TODO: expire pending coop exits after some time so this doesn't become too large
+	// Expire pending (unconfirmed) coop exits older than the configured threshold.
+	// This prevents the set from growing unbounded when transactions are never confirmed
+	// (e.g. evicted from mempool due to low fee or RBF replacement).
+	expiryDays := int(knobs.GetKnobsService(ctx).GetValue(knobs.KnobWatchChainCoopExitPendingExpiryDays, knobs.CoopExitPendingExpiryDays))
+	expiryThreshold := time.Now().AddDate(0, 0, -expiryDays)
+	expiredCount, err := dbClient.CooperativeExit.Delete().
+		Where(
+			cooperativeexit.ConfirmationHeightIsNil(),
+			cooperativeexit.CreateTimeLT(expiryThreshold),
+		).
+		Exec(ctx)
+	if err != nil {
+		return fmt.Errorf("failed to expire stale pending coop exits: %w", err)
+	}
+	if expiredCount > 0 {
+		logger.Sugar().Infof("Expired %d stale pending coop exit(s) older than %d days", expiredCount, expiryDays)
+	}
+
 	if knobs.GetKnobsService(ctx).GetValue(knobs.KnobWatchChainTweakKeysForCoopExitDelayEnabled, 0) > 0 {
 		// Build lists of both normal and reversed TxIDs to handle both endianness
 		confirmedTxIDs := make([]st.TxID, 0, len(confirmedTxHashSet)*2)
diff --git a/spark/so/knobs/knobs.go b/spark/so/knobs/knobs.go
index 100fcc9c3..77637d164 100644
--- a/spark/so/knobs/knobs.go
+++ b/spark/so/knobs/knobs.go
@@ -81,6 +81,7 @@ const (
 	KnobWatchChainMarkExitingNodesEnabled               = "spark.so.watch_chain.mark_exiting_nodes.enabled"
 	KnobWatchChainTweakKeysForCoopExitDelayEnabled      = "spark.so.watch_chain.tweak_keys_for_coop_exit_delay.enabled"
 	KnobWatchChainCoopExitKeyTweakRequiredConfirmations = "spark.so.watch_chain.coop_exit_key_tweak_required_confirmations"
+	KnobWatchChainCoopExitPendingExpiryDays             = "spark.so.watch_chain.coop_exit_pending_expiry_days"
 
 	// CoopExitConfirmationThreshold is the default required L1 confirmation
 	// count for both the watch-chain key-tweak advance and the receiver-claim
@@ -88,6 +89,10 @@ const (
 	// KnobWatchChainCoopExitKeyTweakRequiredConfirmations with this value as
 	// the fallback so they can never disagree when the knob is unset.
 	CoopExitConfirmationThreshold = 6
+	// CoopExitPendingExpiryDays is the default number of days after which a
+	// pending (unconfirmed) cooperative exit is considered stale and deleted.
+	// 14 days matches the default Bitcoin Core mempool expiry (DEFAULT_MEMPOOL_EXPIRY).
+	CoopExitPendingExpiryDays = 14
 
 	// Tokens
 	KnobTokenTransactionV3Enabled = "spark.so.tokens.token_transaction_v3_enabled"
diff --git a/spark/so/utils/btc_address_network.go b/spark/so/utils/btc_address_network.go
index 51897d400..3a5cdd071 100644
--- a/spark/so/utils/btc_address_network.go
+++ b/spark/so/utils/btc_address_network.go
@@ -1,34 +1,17 @@
 package utils
 
 import (
-	"strings"
-
+	"github.com/btcsuite/btcd/btcutil"
 	"github.com/lightsparkdev/spark/common/btcnetwork"
 )
 
-// IsBitcoinAddressForNetwork checks if the given Bitcoin address matches the expected prefix for the specified network.
-// It uses simple prefix matching for common address types (legacy, P2SH, SegWit, Taproot) for each Bitcoin network.
-// TODO: Investigate using btcutil for this instead of using our own.
+// IsBitcoinAddressForNetwork checks if the given Bitcoin address is valid for the specified network.
+// It uses btcutil.DecodeAddress for proper address validation including checksum verification.
 func IsBitcoinAddressForNetwork(address string, network btcnetwork.Network) bool {
-	switch network {
-	case btcnetwork.Mainnet:
-		return hasAnyPrefix(address, "bc1", "3", "1")
-	case btcnetwork.Regtest:
-		return hasAnyPrefix(address, "bcrt", "2", "m", "n")
-	case btcnetwork.Testnet:
-		return hasAnyPrefix(address, "tb1", "2", "m", "n")
-	case btcnetwork.Signet:
-		return hasAnyPrefix(address, "tb1", "sb1", "2", "m", "n")
-	default:
+	params, err := network.Params()
+	if err != nil {
 		return false
 	}
-}
-
-func hasAnyPrefix(address string, prefixes ...string) bool {
-	for _, prefix := range prefixes {
-		if strings.HasPrefix(address, prefix) {
-			return true
-		}
-	}
-	return false
+	_, err = btcutil.DecodeAddress(address, params)
+	return err == nil
 }