The past few months have seen many tech initial public offerings rocket on their opening day and in subsequent weeks. The big question over the next few months will be whether those sterling performances will be maintained after the expiration of lockup restrictions on the sale of shares held by early investors and employees.

Those lockups can exaggerate the initial gains of hot stocks by limiting the shares available to buy. Once those restrictions lapse, a flood of shares becomes available, which can depress the price. Typical is Snowflake, one of the hottest IPOs of the year, whose stock rose more than 200% from its IPO price to highs of $429 in early December. But the expiration of the first phase of lockups in mid-December punctured some of the euphoria and the stock has since trended down, to Thursday’s close of $281.