For more than a year, startup founders have watched in awe and some trepidation as hedge funds and other large investors flooded private startups with big checks, pushing up valuations and making it easier than ever to raise money.

Those freewheeling days may be numbered as a sell-off in public tech stocks bleeds into the startup world. Among the examples of change: Investors are starting to play hardball. Tiger Global Management, one of the biggest funders of private tech startups in the past two years, and some of its peers have been slashing their offers for shares of private software startups, sometimes after founders signed the investment paperwork, people with knowledge of three such deals told The Information.