StubHub, Netskope Said to Begin IPO Marketing as Soon as Monday

A pair of IPO hopefuls are adding to September’s packed calendar, seizing the momentum from a string of well-received debuts as US equity markets near record highs.

Ticket selling platform StubHub Holdings Inc. and cybersecurity firm Netskope Inc. are planning to start formally marketing their initial public offerings as soon as Monday, according to people familiar with the matter.

A listing for New York City-based StubHub could raise at least $1 billion, the people said. The company updated its filing nearly a month ago in a sign that it was restarting plans after a delay earlier this year. The IPO ...