diff --git a/dynamodb/expression.odin b/dynamodb/expression.odin
index 6568a06..d4b4d09 100644
--- a/dynamodb/expression.odin
+++ b/dynamodb/expression.odin
@@ -173,12 +173,14 @@ parse_key_condition_expression :: proc(
 
 	eq_token := next_token(&t) or_return
 	if eq_token != "=" {
+		delete(pk_name) // free on error
 		return
 	}
 
 	pk_value_token := next_token(&t) or_return
 	pk_value, pk_ok := resolve_attribute_value(pk_value_token, attribute_values)
 	if !pk_ok {
+		delete(pk_name) // free on error
 		return
 	}
 
@@ -187,12 +189,14 @@ parse_key_condition_expression :: proc(
 	// Optional "AND ..."
 	if and_token, has_and := tokenizer_next(&t).?; has_and {
 		if !strings.equal_fold(and_token, "AND") {
+			delete(pk_name) // free on error
 			attr_value_destroy(&pk_value)
 			return
 		}
 
 		skc, skc_ok := parse_sort_key_condition(&t, attribute_names, attribute_values)
 		if !skc_ok {
+			delete(pk_name) // free on error
 			attr_value_destroy(&pk_value)
 			return
 		}
@@ -228,12 +232,14 @@ parse_sort_key_condition :: proc(
 	op_token := next_token(t) or_return
 	operator, op_ok := parse_operator(op_token)
 	if !op_ok {
+		delete(sk_name)  // free on error
 		return
 	}
 
 	value_token := next_token(t) or_return
 	value, val_ok := resolve_attribute_value(value_token, attribute_values)
 	if !val_ok {
+		delete(sk_name)  // free on error
 		return
 	}
 
@@ -242,18 +248,21 @@ parse_sort_key_condition :: proc(
 		// IMPORTANT: after allocating `value`, do NOT use `or_return` without cleanup.
 		and_token, tok_ok := next_token(t)
 		if !tok_ok || !strings.equal_fold(and_token, "AND") {
+			delete(sk_name)  // free on error
 			attr_value_destroy(&value)
 			return
 		}
 
 		value2_token, tok2_ok := next_token(t)
 		if !tok2_ok {
+			delete(sk_name)  // free on error
 			attr_value_destroy(&value)
 			return
 		}
 
 		v2, v2_ok := resolve_attribute_value(value2_token, attribute_values)
 		if !v2_ok {
+			delete(sk_name)  // free on error
 			attr_value_destroy(&value)
 			return
 		}
@@ -287,18 +296,21 @@ parse_begins_with :: proc(
 
 	comma := next_token(t) or_return
 	if comma != "," {
+		delete(sk_name)  // free on error
 		return
 	}
 
 	value_token := next_token(t) or_return
 	value, val_ok := resolve_attribute_value(value_token, attribute_values)
 	if !val_ok {
+		delete(sk_name)  // free on error
 		return
 	}
 
 	// after allocating `value`, avoid `or_return` so we can clean up
 	rparen, tok_ok := next_token(t)
 	if !tok_ok || rparen != ")" {
+		delete(sk_name)  // free on error
 		attr_value_destroy(&value)
 		return
 	}
diff --git a/dynamodb/filter.odin b/dynamodb/filter.odin
index 9ca3776..350fda5 100644
--- a/dynamodb/filter.odin
+++ b/dynamodb/filter.odin
@@ -51,6 +51,10 @@ parse_projection_expression :: proc(
 
 		resolved, res_ok := resolve_attribute_name(trimmed, attribute_names)
 		if !res_ok {
+			// Cleanup previously cloned strings
+			for path in result {
+				delete(path)
+			}
 			delete(result)
 			return nil, false
 		}