My saddles have a unique number stamped on the underside by Bates, which I have recorded and the stirrup bars are engraved with my post code, leathers are engraved with my surname. And the trailer has the unique code and postcode engraved on all parts that could be removed and sold separately.
When I bought my youngster I bought a second hand saddle knowing that he would grow. When I cleaned it I noticed it had a postcode stamped in the panel. I called the tack shop where I bought it and asked what I should do, and do you know, they had no idea what the proceedure was! I asked if they had a recieot of purchase and they said no, so technically if the police ever aproached me about it I would be hard pressed to prove ownership.
One of our liveries however is a local horsewatch person and she has the tools to do this so she got her policeman husband to check the records (of course it wasn't a dodgy saddle, shes just like that) and then she struck through the old postcode and put mine on.
Waste of time though as the horse outgrew the saddle in 4 months and it now has 2 wrong postcodes stamped on it!
All my tack is stamped with my postcode, my local crime prevention officer did it for me. I wouldn't think it would be a visual enough deterrant to stop someone taking it but at least it might help recover it.
I'm going to organise a table top tack sale soon, there is a local(ish) lady who marks tack, I'm going to ask her to come, I'll advertise the fact that she'll be there.
Local Horsewatch arranged a tack marking session& I got all my saddles done there. Bridles aren't done though & I've got a couple of decent ones now.