An IPO's Grey Market Premium (GMP) is a non-formal measure of how the market views the company prior to its formal listing. It shows the price, typically higher than the issue price, at which IPO shares are being exchanged informally on the gray market. While a low or negative GMP may signal muted or poor sentiment, a positive GMP implies that investors anticipate the company will list at a premium.
Short-term demand, market sentiment, and trader liquidity are the main drivers of grey market transactions, which are unofficial and unregulated. The premium may change every day depending on the number of subscribers, the state of the market overall, and the news around the business or industry.