In your opinion, when is it appropriate to put your brand on a horse? Obviously if you own it you have every right to brand it but what are your general guidelines from a cultural standpoint?

Bred/raised / Trained /Had a lot of success on/owned for a long time..

For me, I only brand what I raise. And it has to earn the right to pack the brand. I guess, I could also see doing so with something I didn't raise as an indentifying mark if stolen- but I never have.

I also don't own anything I didn't raise unless it's bought for breeding purposes.

We brand everything unless they already have a brand.  We probably do that due to raising cattle and would like a permanant identification mark on everything.  I raise a colt or two or buy them as weanlings. We brand the horses when they are 2.  We buy these horses to use on the ranch and I do some roping. So they aren't purchased for immediate resale, they tend to stick around for awhile until someone wants them more than I do. Usually when they get really useful.....

Only what we raise. We did brand a stud and 1 broodmare we bought, but not anymore. 

My opinion is the breeder should if they do. Other than that, no. I've seen a few of mine with brands on them (I don't brand) and it kinda makes me wonder why. 

We brand horses that we feel represent our name/our training. We have branded horses that we personally started and we have branded some that we bought broke/young but trained and competed. We don't breed/raise but do train and sell several. There are also plenty we don't brand.

We brand all of our foals. We also brand a mare or stud that doesn't have a brand or some kind of identifing marking. If a horse with no markings gets lost or stolen, it's to prove ownership.

We brand what earns it and represents our training.  We've gotten pickier I will say that.

We have one that's not branded, he came to us fully trained but a "problem" horse.  We figure it out (kissing spines) and now would like to sell him as he's ready for someone who is going to use him.  I would like to brand him, just because he's such a sweetheart and a good boy if we do sell him and he gets resold, I'd like to know if he finds himself in a bad spot there's a chance we could be contacted via the brand and either provide guidance to a new owner or get him out of a poor situation like a kill pen - he doesn't deserve that.

I launched a FB page earlier this year to sell horses from (seems to work better than a personal page) and I've had a couple folks reach out about horses they have with the brand. 

We brand everything we are planning on keeping with our registered brand, except for we have one horse that already has 3 brands on so don't think he needs anymore.  we do it for indentifying purposes in case lost or stolen.  We don't raise any

I generally brand everything I own and especially raise.

I brand my all my horses that will be with me for life, if I'm not sure about them when I first get them  then I wont brand for a while untill I'm sure they are here with me for life, I dont buy and sell so if the horse works out for me then its here for life and gets my freeze brand, I wont rebrand one that is all ready carrying a brand. And I would never brand one with my brand thats been trained by someone else to resell it later on down the road, only brand if its unbroke or green and you put all the trainning into this horse yourself. I brand so if my horses get out (lost) or stolen, then I can prove that horse is mine, been down this road once, and that brand can really come in handy.