The pre-open market, also known as the pre-market session or pre-market trading, is a brief period before the regular trading session begins in a stock exchange. Indian market opening time is 9.15 AM. During this time, investors can place orders to buy or sell securities at specific prices. The duration and specific rules of the pre-open market may vary across different exchanges. generally Indian market  preopen timing is 9 AM to 9.07 AM. after 9.08 AM  some can check the open price on NSE website or broker terminal on the basis of demand and supply on that particular day.

The purpose of the pre-open market is to facilitate price discovery and allow market participants to react to significant overnight news or events that may impact the opening price. It provides an opportunity for investors to place orders and for the exchange to determine the opening price based on the supply and demand dynamics of the pre-open session.

 In the pre-open market, the order types and order entry mechanisms may differ from the regular trading session. Typically, limit orders are accepted during this period, where investors specify the maximum price at which they are willing to buy or the minimum price at which they are willing to sell a security. Market orders, which are orders to buy or sell at the prevailing market price, are generally not allowed during the pre-open session. 

As for who can place orders in the pre-open market, it depends on the rules and regulations of the specific exchange. In general, institutional investors, retail investors, and market makers may participate in the pre-open session. 

However, some exchanges may have specific eligibility criteria or restrictions on who can participate in pre-market trading. It's important to note that the pre-open market has limited trading hours and lower liquidity compared to the regular trading session. Therefore, price movements and executed trades during the pre-open market may not necessarily reflect the opening price or subsequent trading activity in the regular session.

 Individual investors should familiarize themselves with the rules and procedures of their respective exchanges regarding pre-open market trading and consider the potential risks and limitations associated with participating in this session. Consulting with a financial advisor or broker can provide further guidance on pre-market trading and its suitability for specific investment strategies.