Stocks making the biggest moves midday: Halliburton, Warner Bros. Discovery, Oracle and more

cnbc.com:

Occidental Petroleum, Halliburton, EOG Resources — Shares of oil and gas companies were higher Tuesday after Saudi Arabia earlier extended its one million barrel per day voluntary crude oil production cut until the end of the year. Occidental Petroleum gained about 3.3%. Halliburton added 2.8% and EOG Resources rose 3.1%. The cut, which led oil prices higher during the day, adds to other voluntary crude output declines that some members of OPEC have put in place until the end of 2024.

Oracle — The software stock climbed 2% on the back of an upgrade to overweight from equal weight by Barclays. The firm said the company's cloud business should be helped by artificial intelligence.

Airbnb — Shares rose 8% on the back of S&P Dow Jones Indices' Friday announcement that the stock would join the S&P 500 starting Sept. 18. The S&P 500 is widely tracked by large index funds, which could create buying pressure on Airbnb's stock in the weeks ahead.

Blackstone — Shares of the asset management company gained 4% on news that the stock will join the S&P 500 before the open on Sept. 18, as part of a quarterly rebalance for S&P Indices.

Warner Bros. Discovery — The media stock added 3% during midday trading after Warner Bros. said it still expects to hit its net leverage target, despite taking a hit of $300 million to $500 million in its adjusted earnings before interest, taxes, depreciation and amortization. That puts its adjusted earnings in the full-year range of $10.5 billion to $11 billion. Warner Bros. said its adjusted full-year expectation assumes the financial effect of the writers and actors strikes will persist through the end of the year.

NextGen Healthcare — Shares of the health-care company popped nearly 7% Tuesday