public static boolean isValidGroupAddress(final int address) {
        if (!isAddressInRange(address))
            return false;

        final int b0 = address >> 8 & 0xFF;
        final int b1 = address & 0xFF;

        final boolean groupRange = b0 >= 0xC0 && b0 <= 0xFF;
        final boolean rfu = b0 == 0xFF && b1 >= 0x00 && b1 <= 0xFB;
        final boolean allNodes = b0 == 0xFF && b1 == 0xFF;

        return groupRange && !rfu && !allNodes;
    }
Returns true if the its a valid group address

@param address 16-bit address
@return true if the address is valid and false otherwise
mesh/src/main/java/no/nordicsemi/android/mesh/utils/MeshAddress.java