How 'America's most valuable stallion' makes over $35 million a year without setting hoof on the track

America's most valuable stallion is retired and still makes over $35...

Making over $35 million a year as a retiree is rather impressive — and it's maybe even more so when the retiree in question is a horse.

But it's become the norm for the racing-stallion-turned-stud known as Tapit.

The thoroughbred breeds with up to 125 mares a year at a record stud fee of $300,000 per mare, which brings Tapit's yearly earnings to over $35 million. "He's the most valuable stallion at stud in America," says Michael Hernon, director of sales at Gainesway, the Lexington, Ky., farm where Tapit resides.

Tapit takes a stroll at the Gainesway Farm in Lexington, Ky., where he headlines the stallion roster.
Ian Tapp | Gainesway

It's a staggering figure considering the top-earning racehorse in 2016 netted just over $4 million in total earnings at the track, according to BloodHorse.

But in the big business of thoroughbred racing, sometimes the real money is made in the breeding shed. Owners pay top dollar to ensure they are getting horses from a lineage of proven winners. Since 2014, Tapit has held the title of the nation's leading sire, meaning that the stallion's progeny have earned the most on the track every year for the previous three years. Most recently, in 2016, Tapit's progeny made $19.9 million in total earnings.

Even the stud fee of recent Triple Crown winner American Pharoah fell short of Tapit's in 2016, since, as yet, Pharoah has no track record off of the track.

Tapit grazes in the barn area at Churchill Downs on April 29, 2004, in Louisville, Ky.
Getty Images |

As an active racehorse, Tapit only won three of his six races over a career plagued by lung infections. When he retired to stud in 2004, his fee was a mere $15,000, according to Racing Post. Things changed as his progeny began notching wins around the circuit. His subsequent foals won more races, and his stud fee increased to $80,000 in 2011 and $150,000 in 2014 — a full ten-fold increase from where he began a decade before.

"He's got very strong libido and fertility and everyone knows who's the boss down in the breeding shed," Hernon says.

At 16 years old, Tapit seems to have many happy years ahead of him. "He can still breed two, three mares a day," says Gainesway Stallion Manager Carl Buckler. "No problem at all."

In 2014, Racing Post reported a single share in Tapit that came with a breeding right for the duration of the stud's career was sold for $2.8 million, valuing Tapit's total worth at an estimated $140 million.

Watch CNBC's "The Filthy Rich Guide," Wednesday, May 31st at 10 PM/ET.

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