Short answer

You see bids and offers at 0 in the market depth because the exchange initially prices all market orders at 0 during specific trading sessions.

When this happens

Pre-open session (9:00 AM to 9:15 AM): All market orders you place during the pre-open session (both regular and After Market Orders or AMO) start at 0 price. The exchange terms these ‘At the Open’ or ATO orders. Your orders remain at this price until:

Order matching occurs during the random closure period (9:07 AM to 9:08 AM)

The exchange determines the equilibrium price

The market depth updates immediately after price discovery (around 9:08 AM)

Periodic call auction sessions: You will also see 0 displayed in bids and offers for stocks traded in the periodic call auction category. During auction sessions, the exchange initially prices market orders at 0, similar to the pre-market session.

Example scenario

  • The price for MRF was 0 before the equilibrium price discovery.
  • After 9:08 AM, the market depth was updated to show the equilibrium price.