yep - as it stands now, a microchip is useless if your horse is stolen and shipped off to auction or slaughter. But for identification purposes when you critter gets loose (trees fall on fences ALL of the time) and someone else tries to claim him?
Let me tell you this - happened once in my area - a guy up the road lost a sorrel mare. Found the fence down (car ran into it during the night) and reported his horse missing with every authority that could do something about it - law, animal shelter, auction barns, etc. Three months later, he sees his horse across the street in a pasture behind his neighbor's house - purely by accident, since the paddock was hidden behind the house - couldn't see it from the road.
He asked the guy why he had his horse when he was one of the first people he checked with when his horse turned up missing? He said prove it is your horse! So the 'good' guy calls the local authorities - they show up together at the house with the horse and the sheriff asks the 'bad guy' to prove that this horse is his? So the bad guy pulls out a coggins - of course it is only 3 months old, and the sheriff stated that current coggins paperwork is as good as gold for proof of ownership here - the 'good guy' was going to have to do better - so the 'good guy' found some pictures of his neice riding the mare earlier that year and matched with the fact that the mare's new coggins fit the timeline that the fence was broken down, the sheriff let the 'good guy' get his horse back.
Long story - sorry - but point is, for most authorities who don't know zip about horses - especially here in TX, whoever has the most current coggins wins.
I say a microchip trumps a coggins for ID any time, even registration papers - doesn't hurt to be safe.
Clippityclop is finally getting to spend some time in the saddle!