IPO stands for "Initial Public Offering." In the real world, this is when a private company offers its shares to be bought by the public by way of listing the company's shares on a stock exchange.
On the simExchange, an IPO is when a new stock or futures contract becomes available for trading. These IPOs occur through two phases. Each IPO phase begins at 11:00 AM Pacific Time. The schedule for IPOs is always posted on the simExchange Official Blog.
In IPO Phase 1, we seek to determine the market price for the stock or futures contract. To do this, the automated market maker is disabled for 48 hours and all trading is conducted between human traders so that only prices people are willing to trade at are available. To participate in IPO Phase 1, players must enable Advanced Trading Mode so that they can specify the price they wish to trade at. More about IPO Phase 1 is explained in the article Discovering an IPO price.
After 48 hours, IPO Phase 2 begins. In Phase 2, bid and ask prices are determined from the trading activity in IPO Phase 1 and then fixed for 24 hours. This means that you can purchase the stock or futures contract at the same price any time in the 24 hour period no matter what time you log on. The same goes for short selling the stock or futures contract. After 24 hours, IPO Phase 2 ends and normal trading begins.