Stud fees for stallions that enter breeding can range from $2,500 to $300,000 per mare in the United States,[9] and from £2000 pounds[10] to £75,000 or more in Britain.
[12] In the 1980s, Northern Dancer's stud fee reached $1 million, an amount four to five times other stallions and a record that still stands in 2009.
[13] The highest price paid at auction for a Thoroughbred was set in 2006 at $16,000,000 for a two-year-old colt named The Green Monkey,[14] who was a descendant of Northern Dancer.
Record prices at auction often grab headlines, though they do not necessarily reflect the animal's future success; in the case of The Green Monkey, injuries limited him to only three career starts before being retired to stud in 2008, and he never won a race.
The most recent common ancestor in the sire line of all thirty-three horses on this list is Phalaris, all via Pharos except two—Meydan City and King's Consul—via Sickle.