Domestic stock markets opened flat on Tuesday as indices stuck between selling by foreign portfolio investors (FPIs) and buying by domestic institutions. The indices continue to test record levels but have failed to sustain gains above the all-time high marks.

The Nifty 50 index opened at 25,998.50 with a gain of 39 points or 0.15 per cent, while the BSE Sensex opened at 85,008.93, gaining 108.22 points or 0.13 per cent.