ECO C99: Ruy Lopez

ECO C99 is part of volume C — Open Games. The Lichess chess-openings dataset files one named line under it. It is Ruy Lopez: Closed, Chigorin Defense, Panov System: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7 6. Re1 b5 7. Bb3 d6 8. c3 O-O 9. h3 Na5 10. Bc2 c5 11. d4 Qc7 12. Nbd2 cxd4 13. cxd4.

That position has come up in 35,485 Lichess games between players rated 1600 to 2500: White won 46.5%, 6.5% were drawn and Black won 47.0%.