ECO E43 · Nimzo-Indian Defense
Nimzo-Indian Defense: St. Petersburg Variation
The position after 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6.
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 b6
Nimzo-Indian Defense: St. Petersburg Variation is filed under ECO E43, a variation of Nimzo-Indian Defense. It is the position after 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 b6 — 8 half-moves in, with White to move. Named theory ends here; beyond this the position is yours to work out.