I'm new to these lists. To quote DFR: These standings provide a measurement of a sire’s ability to produce high-quality horses, not necessarily the most winners or highest earners. The results are interesting, especially for the 100+ horses.
http://www.drf.com/breeding/sire-list-beyer/
2017 leaders with runners over Beyer 90+:
1. War Front
2. Kitten's Joy
3. Tapit
4. Giant's Causeway
5. Candy Ride
2017 leaders with runners over Beyer 100+:
1. Kitten's Joy
2. Curlin
3. Lookin at Lucky
4. Dubawi
5. Scat Daddy (tie)
5. War Front (tie)
5. English Channel (tie)
5. Stormy Atlantic (tie)