This is about why they mark and then the link explains how to fix it... all dogs are capable of marking. This includes ones that are spayed/neutered. Much like the miners during the Gold Rush, dogs are territorial animals. They "stake a claim" to a particular space, area, or object by marking it, using a variety of methods at different levels of intensity.
For example, a dog may bark to drive away what he perceives to be intruders in his territory. Some dogs may go to the extreme of urinating or defecating on something to say "mine!." Pets aren't people
Dogs don't urinate or defecate out of spite or jealousy. If your dog urinates on your baby's diaper bag, it's not because he is jealous of, or dislikes, your baby. The unfamiliar scents and sounds of a new baby in the home are stressing him out a bit and he feels the need to reaffirm his claim on his territory.
Likewise, if your dog urinates on your new boyfriend's backpack, it doesn't reflect his opinion of your taste in men. Instead, he has perceived the presence of an "intruder," and is letting the intruder know this territory belongs to him. Urine-marking is not house soiling
House soiling is when your dog empties his bladder or his bowels inside the house. There are a few reasons he may do this.
He's not housebroken. He has a medical issue. He's terrified and has lost control of his bladder and/or bowels.
Urine-marking, on the other hand, is a territorial behavior. Your dog feels the need to assert his dominance or ease his anxiety by laying out his boundaries. He does this by depositing small amounts of urine on anything he feels belongs to him—the furniture, the walls, your socks, etc.
Urine-marking is most often associated with male dogs, but females may do it, too. Leg-lifting is the primary way of marking, but even if your pet doesn't lift his leg, he may still be marking.
The amount of urine is small and is found primarily on vertical surfaces, but dogs do sometimes mark on horizontal surfaces.
Reasons for urine-marking
Your dog isn't spayed or neutered. Unneutered dogs are much more assertive and prone to marking than neutered ones. There's a new pet in the household. Another pet in your home is not spayed or neutered. Even spayed or neutered animals may mark in response to other intact animals in the home. Your dog has conflicts with other animals in your home. When there's instability in the pack dynamics, a dog may feel a need to establish his place by marking his territory. There's someone new in the house (spouse, baby, roommate); your dog puts his scent on that person’s belongings as a way of proclaiming that the house is his. There are new objects in the environment (a shopping bag, a visitor's purse) that have unfamiliar smells or another animal's scent. Your dog has contact with other animals outside your home. If your pet sees another animal through a door or window, he may feel a need to mark his territory.
What you can do
Now that you know why dogs mark their territory with urine, here's how to prevent it from happening in your home »
Urine-Marking Behavior: How to Prevent It
You mark your stuff by putting your name on it; your dog marks his with urine. We've covered why dogs mark territory,now here's how to prevent urine-marking behaviors before they happen in your house.
Before doing anything else, take your dog to the veterinarian to rule out any medical causes for the urine-marking behavior. If he gets a clean bill of health, use the following tips to make sure he doesn't start marking his territory.
Spay (or neuter) first Spay or neuter your dog as soon as possible. The longer a dog goes before neutering, the more difficult it will be to train him not to mark in the house. Spaying or neutering your dog should reduce urine-marking and may stop it altogether.
But if he has been marking for a long time, a pattern may already be established. Because it has become a learned behavior, spaying or neutering alone won't solve the problem. Use techniques for housetraining an adult dog to modify your dog's marking behavior.
Make previously soiled areas inaccessible or unattractive.If this isn't possible, try to change the significance of those areas to your pet. Feed, treat, and play with your pet in the areas where he marks.
Keep objects likely to cause marking out of reach.Items such as guests' belongings and new purchases should be placed in a closet or cabinet.
Resolve conflicts between animals in your home. If you've added a new cat or new dogto your family, follow our tip sheets to help them live in harmony.
Restrict your dog's access to doors and windowsso he can't observe animals outside. If this isn't possible, discourage the presence of other animals near your house.
Make friends.If your pet is marking in response to a new resident in your home (such as a roommate or spouse), have the new resident make friends with your pet by feeding, grooming, and playing with your pet. If you have a new baby, make sure good things happen to your pet when the baby is around.
Watch your dog when he is indoorsfor signs that he is thinking about urinating. When he begins to urinate, interrupt him with a loud noise and take him outside. If he urinates outside, praise him and give him a treat.
When you're unable to watch him, confine your dog (a crateor small room where he has never marked) or tether him to you with a leash.
Have your dog obey at least one command(such as "sit") before you give him dinner, put on his leash to go for a walk, or throw him a toy.
If your dog is marking out of anxiety, talk to your vet about medicating him with a short course of anti-anxiety medication. This will calm him down and make behavior modification more effective.
Consult an animal behaviorist for help with resolving the marking issues.
What not to do Don't punish your pet after the fact. Punishment administered even a minute after the event is ineffective because your pet won't understand why he is being punished.
If you come home and find that your dog has urinated on all kinds of things, just clean up the mess. Don't take him over to the spots and yell and rub his nose in them. He won't associate the punishment with something he may have done hours ago, leading to confusion and possibly fear.