Corrects year of GameStop short squeeze to 2021, not 2020, in paragraph 4

By Ateev Bhandari

June 5 (Reuters) - Robinhood HOOD.O executive Steve Quirk on Thursday credited retail investors with helping the market rebound after a sharp plunge in April, adding that young self-directed traders were increasingly making trades outside traditional hours.

His comments came in reference to the market turmoil that followed U.S. President Donald Trump's announcement of sweeping tariffs on Liberation Day earlier this year.

"This is the second occurrence where I would argue retail came to the rescue of the market. COVID (was) probably the first," said Quirk, Robinhood's chief brokerage officer, at the Piper Sandler Global Exchange & Trading Conference in New York.

Retail investors have evolved into a notable market force since the GameStop short-squeeze of 2021, buying $4.7 billion in stocks on April 3, the highest level over the past decade, according to JPMorgan estimates.

This was a day after Trump launched his erratic tit-for-tat tariff campaign, which roiled markets worldwide, scuttled dealmaking, and dampened consumer sentiment.

Another way retail investors are changing the markets is through overnight trading, which is growing in popularity as global demand for U.S. stocks surges.

Robinhood's users, especially those in their 30s, "do the research and homework in the evening," and expect to be able to make trades whenever they wish, Quirk said.

Trading volume outside traditional hours has also spiked sharply as a tumultuous period of U.S. policy in recent months has kept markets on edge. There have often been steep selloffs in after-hour trading if material pivots on trade policy were announced late in the day.

Robinhood estimates up to a quarter of its total daily trading volume on its busiest days comes from outside traditional market hours. May was the biggest month at the company for overnight trading, by volume, according to Quirk.

"You will look back in a couple years and laugh at the notion that we waited until 9:30 Eastern for trading to start," said Quirk.

Robinhood and competitor Interactive Brokers IBKR.O have been offering overnight trading for limited equities for a few years now.

(Reporting by Ateev Bhandari in Bengaluru; Editing by Leroy Leo)

((Ateev.Bhandari@thomsonreuters.com;))