To batch process signatures in Lightroom, there are two programs that we need aside from Lightroom.
1. LR2/Mogrify – a LR post-process plugin that can embellish your images as they are exported from Lightroom (more info here)
2. ImageMagick – a collection of powerful, freeware command line utilities for processing images and LR2/Mogrify uses this to process the Image (more info here)

First, you need to download and install ImageMagick and LR2/Mogrify. The LR2/Mogrify trial version available on the site is limited to export only 10 pictures so it would be best if you donate the project to get the LR2/Mogrify full version registration code. I just did and I got my registration code. You are going to envy me once you realize that exporting 10 photos at a time is a pain in the arse.

Once you have downloaded, LR2/Mogrify and ImageMagick, follow this link for the installation guide.

Here is our checklist:
1. Adobe LightRoom – check!
2. LR2/Mogrify – installed!
3. ImageMagick – installed!
4. A lot of photos – check!

Now, you have edited your pictures and ready to “own” it (I meant,watermark);
1. Select the photos that you want to export and watermark.
2. Click on File then Export  (Ctrl+Shift+E)
3. Now you should see newly added options to Lightroom export module. You will have all the options on that you can do to your images for post-processing.

Select your desired settings for fonts, font size, position and others. After that, click on EXPORT and voila! You have now watermarked a number of photos.

You may check your exported photos now and check if the signatures/watermarks look ok for your taste. You may redo your settings. That is it! As easy as that, you will now be able to put a signature and watermark on a 100, 1000 or even 1,000,000 photos!

If you like my tutorial and you think it has helped you a lot, you BUY ME A BEER! Any amount will do.