diff --git a/hardware/arduino/cores/arduino/WString.cpp b/hardware/arduino/cores/arduino/WString.cpp
index 3e813316e..c6839fc0d 100644
--- a/hardware/arduino/cores/arduino/WString.cpp
+++ b/hardware/arduino/cores/arduino/WString.cpp
@@ -500,7 +500,7 @@ int String::lastIndexOf( char theChar ) const
 
 int String::lastIndexOf(char ch, unsigned int fromIndex) const
 {
-	if (fromIndex >= len || fromIndex < 0) return -1;
+	if (fromIndex >= len) return -1;
 	char tempchar = buffer[fromIndex + 1];
 	buffer[fromIndex + 1] = '\0';
 	char* temp = strrchr( buffer, ch );
@@ -516,7 +516,7 @@ int String::lastIndexOf(const String &s2) const
 
 int String::lastIndexOf(const String &s2, unsigned int fromIndex) const
 {
-  	if (s2.len == 0 || len == 0 || s2.len > len || fromIndex < 0) return -1;
+  	if (s2.len == 0 || len == 0 || s2.len > len) return -1;
 	if (fromIndex >= len) fromIndex = len - 1;
 	int found = -1;
 	for (char *p = buffer; p <= buffer + fromIndex; p++) {
diff --git a/libraries/Servo/Servo.cpp b/libraries/Servo/Servo.cpp
index acac29a86..dbe3bedd9 100755
--- a/libraries/Servo/Servo.cpp
+++ b/libraries/Servo/Servo.cpp
@@ -298,7 +298,7 @@ void Servo::writeMicroseconds(int value)
 {
   // calculate and store the values for the given channel
   byte channel = this->servoIndex;
-  if( (channel >= 0) && (channel < MAX_SERVOS) )   // ensure channel is valid
+  if( (channel < MAX_SERVOS) )   // ensure channel is valid
   {  
     if( value < SERVO_MIN() )          // ensure pulse width is valid
       value = SERVO_MIN();