Midday movers: Costco, Warner Bros. Discovery, Rivian and more

Investing.com -- U.S. stocks erased early gains and turned lower, weighed by concerns about higher for longer interest rates and the rising potential for a government shutdown this weekend.

Here are some of the biggest U.S. stock movers today:

• Costco (NASDAQ:COST) stock rose 1.5% as fourth quarter results beat expectations on both the top and bottom lines.

• Warner Bros Discovery Inc (NASDAQ:WBD) shares rose 2.2% after Hollywood's writer's union ended its strike against major studios and streaming platforms, with a new tentative three year contract. Shares of Paramount Global Class B (NASDAQ:PARA) rose 1.9%.

• Rivian (NASDAQ:RIVN) stock fell 0.4% after the EV manufacturer announced plans to use subscription models for monetizing various features in cars.

• Amazon (NASDAQ:AMZN) stock fell 0.9% after the Federal Trade Commission filing a long-awaited antitrust lawsuit against the online retail giant.

• Zions Bancorporation (NASDAQ:ZION) stock fell 0.9% after Morgan Stanley downgraded the lender to ‘underweight’ from ‘equal weight’, citing an elevated valuation after gains of over 70% since May lows.

• Mattel (NASDAQ:MAT) stock rose 3.7% after the toymaker posted a surprise profit in the second quarter and its sales exceeded market expectations, while the box office success of the "Barbie" movie is likely to help drive doll sales in the second half of the year.

• Marriott International (NASDAQ:MAR) stock rose 0.7% after the hotel operator forecast two-year annualized global revenue per available room growth of 3% to 6% by 2025, expecting resilient international travel demand.

• MillerKnoll (NASDAQ:MLKN) stock rose 28.7% after the upmarket furniture-maker raised its full-year profit outlook.

• Cardiff Oncology (NASDAQ:CRDF) stock rose 4.3% after the biotechnology company announced favorable data from two cancer drug trials.