diff --git a/src/main/scala/net/snowflake/spark/snowflake/ServerConnection.scala b/src/main/scala/net/snowflake/spark/snowflake/ServerConnection.scala
index 473b814d..f8118d70 100644
--- a/src/main/scala/net/snowflake/spark/snowflake/ServerConnection.scala
+++ b/src/main/scala/net/snowflake/spark/snowflake/ServerConnection.scala
@@ -135,6 +135,14 @@ private[snowflake] object ServerConnection {
     serverConnection
   }
 
+  private def putProperty(jdbcProperties: Properties, key: Object, value: Object): Unit = {
+    if (value != null) {
+      jdbcProperties.put(key, value)
+    } else {
+      throw new IllegalArgumentException(s"Invalid JDBC property: ${key.toString}")
+    }
+  }
+
   private def createJDBCConnection(params: MergedParameters): Connection = {
     // Derive class name
     val driverClassName = JDBC_DRIVER
@@ -155,42 +163,42 @@ private[snowflake] object ServerConnection {
     val jdbcProperties = new Properties()
 
     // Obligatory properties
-    jdbcProperties.put("db", params.sfDatabase)
-    jdbcProperties.put("schema", params.sfSchema) // Has a default
+    putProperty(jdbcProperties, "db", params.sfDatabase)
+    putProperty(jdbcProperties, "schema", params.sfSchema) // Has a default
     if (params.sfUser != null) {
       // user is optional when using Oauth token
       jdbcProperties.put("user", params.sfUser)
     }
     params.privateKey match {
       case Some(privateKey) =>
-        jdbcProperties.put("privateKey", privateKey)
+        putProperty(jdbcProperties, "privateKey", privateKey)
       case None =>
         // Adding OAuth Token parameter
         params.sfToken match {
           case Some(value) =>
-            jdbcProperties.put("token", value)
-          case None => jdbcProperties.put("password", params.sfPassword)
+            putProperty(jdbcProperties, "token", value)
+          case None => putProperty(jdbcProperties, "password", params.sfPassword)
         }
     }
-    jdbcProperties.put("ssl", params.sfSSL) // Has a default
+    putProperty(jdbcProperties, "ssl", params.sfSSL) // Has a default
     // Optional properties
     if (params.sfAccount.isDefined) {
-      jdbcProperties.put("account", params.sfAccount.get)
+      putProperty(jdbcProperties, "account", params.sfAccount.get)
     }
     if (params.sfWarehouse.isDefined) {
-      jdbcProperties.put("warehouse", params.sfWarehouse.get)
+      putProperty(jdbcProperties, "warehouse", params.sfWarehouse.get)
     }
     if (params.sfRole.isDefined) {
-      jdbcProperties.put("role", params.sfRole.get)
+      putProperty(jdbcProperties, "role", params.sfRole.get)
     }
     params.getTimeOutputFormat match {
       case Some(value) =>
-        jdbcProperties.put(Parameters.PARAM_TIME_OUTPUT_FORMAT, value)
+        putProperty(jdbcProperties, Parameters.PARAM_TIME_OUTPUT_FORMAT, value)
       case _ => // No default value for it.
     }
     params.getQueryResultFormat match {
       case Some(value) =>
-        jdbcProperties.put(Parameters.PARAM_JDBC_QUERY_RESULT_FORMAT, value)
+        putProperty(jdbcProperties, Parameters.PARAM_JDBC_QUERY_RESULT_FORMAT, value)
       case _ => // No default value for it.
     }
 
@@ -200,25 +208,25 @@ private[snowflake] object ServerConnection {
     // Adding Authenticator parameter
     params.sfAuthenticator match {
       case Some(value) =>
-        jdbcProperties.put("authenticator", value)
+        putProperty(jdbcProperties, "authenticator", value)
       case _ => // No default value for it.
     }
 
     // Always set CLIENT_SESSION_KEEP_ALIVE.
     // Note, can be overridden with options
-    jdbcProperties.put("client_session_keep_alive", "true")
+    putProperty(jdbcProperties, "client_session_keep_alive", "true")
 
     // Force DECIMAL for NUMBER (SNOW-33227)
     if (params.treatDecimalAsLong) {
-      jdbcProperties.put("JDBC_TREAT_DECIMAL_AS_INT", "true")
+      putProperty(jdbcProperties, "JDBC_TREAT_DECIMAL_AS_INT", "true")
     } else {
-      jdbcProperties.put("JDBC_TREAT_DECIMAL_AS_INT", "false")
+      putProperty(jdbcProperties, "JDBC_TREAT_DECIMAL_AS_INT", "false")
     }
 
     // Add extra properties from sfOptions
     val extraOptions = params.sfExtraOptions
     for ((k: String, v: Object) <- extraOptions) {
-      jdbcProperties.put(k.toLowerCase, v.toString)
+      putProperty(jdbcProperties, k.toLowerCase, v.toString)
     }
 
     // Only one JDBC version is certified for each spark connector.
@@ -234,7 +242,8 @@ private[snowflake] object ServerConnection {
     // For more details, refer to PROPERTY_NAME_OF_CONNECTOR_VERSION
     // NOTE: From JDBC 3.13.3, the client info can be set with JDBC properties
     // instead of system property: "snowflake.client.info".
-    jdbcProperties.put(SFSessionProperty.CLIENT_INFO.getPropertyKey, Utils.getClientInfoString())
+    putProperty(jdbcProperties, SFSessionProperty.CLIENT_INFO.getPropertyKey,
+      Utils.getClientInfoString())
 
     val conn: Connection = DriverManager.getConnection(jdbcURL, jdbcProperties)