How Do Stud Fees Work? Baeza, Puca's Pedigree and 'Stands and Nurses'

The news: Baeza is retired to stud at Spendthrift

How do stud fees work? A stud fee is the price a mare owner pays a stallion's owner to breed a mare to him, and with a "stands and nurses" fee the full amount is owed only once a live foal stands up and nurses.

On Oct. 6, 2026, Spendthrift Farm announced that Baeza, winner of the 2025 Pennsylvania Derby (G1), has retired from racing. He'll stand the 2027 breeding season in Kentucky for $25,000 stands and nurses.

His announcement makes a good case study. Here's the résumé breeders will be looking at:

• Race record: 2 wins, 4 seconds and 4 thirds from 13 starts, with $2,344,700 in earnings. He retires sound at age 4.
• Big days: He won the Pennsylvania Derby by 2¼ lengths. He was second in the Santa Anita Derby and third in both the 2025 Kentucky Derby and Belmont Stakes.
• At 4: He was second in the Stephen Foster (G1) and third in the Jockey Club Gold Cup (G1) on Sept. 18.
• Pedigree: He's by McKinzie out of Puca, a daughter of Big Brown. That makes him a half-brother to Mage (2023 Kentucky Derby) and Dornoch (2024 Belmont Stakes).
• Sale history: He sold for $1.2 million at the 2023 Keeneland September yearling sale.

Spendthrift's general manager, Ned Toffey, called him a rare combination of talent, pedigree and looks. That sentence is a fair summary of what goes into a stud fee.

How do stud fees work?

A stud fee is the price a mare owner pays the stallion's owner for one breeding to that stallion. The fee covers the mating itself. Board for the mare, vet care and shipping are usually billed separately.

The stallion's owner (often a farm or a group of shareholders) publishes the fee before the season. Breeders then "book" their mares, and the farm accepts or declines each one. Every season has a limited number of slots, which is why popular stallions fill up.

A few terms you'll see in every stallion ad:

• Stand (verb): A stallion "stands" at the farm where he lives and covers mares. Baeza will stand at Spendthrift.
• Book: The list of mares a stallion breeds in one season.
• First crop: His first group of foals. A freshman sire is a stallion whose first crop is racing as 2-year-olds.
• Private: Some farms don't publish a fee and negotiate each mare instead.

What 'stands and nurses' means

Stands and nurses (S&N) is the most common kind of live foal guarantee. The mare owner only owes the full fee once the foal is born, stands up and nurses from its mother.

If the mare doesn't get in foal, loses the pregnancy or the foal can't stand and nurse, the fee generally isn't owed. Contracts often let the owner breed the same mare back the next season instead. That shifts much of the biological risk onto the stallion's side.

Always read the actual contract, because details vary from farm to farm:

1. When payment is due. Some contracts bill after the foal arrives. Others ask for payment earlier and refund it if there's no live foal.
2. What triggers a refund or a return breeding. It might be a slipped pregnancy, a mare that doesn't conceive, or a sold mare.
3. Vet paperwork. A farm may ask for proof that the mare is healthy and checked before she ships.
4. Mare care costs. Board, vet checks and foaling are separate from the stud fee.
5. Deadlines. There are dates for reporting a barren mare or a lost foal.

How a farm sets a first-year stud fee

A brand-new stallion has no foals on the track, so his first fee is an educated bet on what breeders will pay. Farms weigh several things.

Race record

Grade 1 wins carry the most weight, and placings in the classics help. Baeza won a Grade 1 race and placed in two Triple Crown races. He also stayed competitive at the top level at age 4, and he retires sound.

Pedigree, especially the dam's family

The sire matters, but the mare's side is often what makes breeders sit up. Puca is the dam of three Grade 1 winners and was named 2025 Broodmare of the Year by the Thoroughbred Owners and Breeders Association. She sold for $5 million at the 2025 Fasig-Tipton November Sale (see our Fasig-Tipton November guide).

Being a half-brother to Mage and Dornoch means Baeza shares a dam with two classic winners. Half-siblings in Thoroughbred talk share the same mother.

Conformation and looks

Breeders inspect stallions in person, judging their build, balance and the way they move. TDN reports that Baeza will be available for inspection in the coming weeks.

Sire line and market demand

Farms also look at what buyers want. That includes which sire lines are popular, whether a horse brings speed or stamina, and how his foals might sell at auction. Commercial breeders often plan to sell the foal as a yearling, so fashion matters.

Why new stallions often start mid-market

A first-year fee usually sits in the middle of the market, well below the most proven sires in Kentucky. That's deliberate:

• Nothing has been proven yet. A sire's real test is his foals' racing results, and those take years to arrive.
• Volume matters. A fair price attracts a big, high-quality book of mares, which gives the stallion his best shot.
• Fees move with results. Once his foals sell and race, the fee can rise or fall each year.

The timeline from first season to first race

All Northern Hemisphere Thoroughbreds turn a year older on January 1, whatever their real birthday. Mares carry for about 11 months. That's why the season starts around mid-February, so foals arrive early in the following year.

That's why the first fee is set years before anyone knows how the stallion's foals will run.

Why Thoroughbreds are bred by live cover only

Unlike many breeds, Thoroughbreds must be conceived by live cover, meaning a natural mating. Under the international stud book rules, a foal produced by artificial insemination, embryo transfer or cloning can't be recorded as a Thoroughbred, so it can't race as one.

In practice, the mare travels to the stallion's farm, often with her current foal at her side. Veterinarians time each visit to the mare's cycle and check her afterward to confirm pregnancy.

Live cover is one reason stud fees exist the way they do. A stallion can only cover a limited number of mares in a season, so each slot has real value.

What to watch next

• Inspections this fall. Breeders will visit Spendthrift to see Baeza in person.
• Fall sales. Mares sell in foal at events like the November mixed sales. Buyers often note which stallion a mare is covered by.
• The 2027 season. It opens in mid-February. Spendthrift is the source for any updates to Baeza's fee or terms.
• Learn the lingo. Our glossary covers terms like dam, sire and colt, and the breeds hub explains the Thoroughbred itself.

Next time you see a "retired to stud" headline, look for four things: the fee, the guarantee, the dam's family and the year the first crop will race.