Wall Street turned to losses on Monday after starting the day higher on US-China trade talks optimism. Technology and pharmaceutical sectors fell, with the Nasdaq 100 falling more than half a percentage point.

The Dow Jones Industrial Average was flat, trading 0.02% in the red at 12:43 pm ET. Merck led the losses after it was announced that investors who buy Merck stocks starting from September 12th will not be able to receive dividends. The pharmaceutical company dropped 3.73% at 12:29 pm ET.

Nasdaq 100 fell 0.49% at 12:46 pm ET with an array of stocks dropping over 3%, including PayPal Holdings, Intuit, MercardoLibre, Regeneron Pharmaceuticals and Workday.

The S&P 500 lost 0.20% at 12:48 pm ET as MarketAxess Holdings plummeted 10.39% at 12:46 am ET after it was revealed that Natixis increased its share in the company by 91.8%.