Check out the companies making headlines in midday trading. Upstart Holdings — Stock in the artificial intelligence lending platform tumbled more than 26% after missing third-quarter sales and earnings estimates. The company reported an adjusted loss of 5 cents per share on $134.5 million in revenue, against estimates from analysts polled by FactSet of a a loss of 2 cents and $139.6 million. Biogen — Stock in the biotech company fell more than 4% after third-quarter sales and earnings topped analyst estimates. The maker of Tysabri for multiple sclerosis slashed its annual profit forecast, however, due to costs tied to Alzheimer’s treatment Leqembi and the acquisition of Reata Pharmaceuticals last month. Occidental Petroleum — Shares of the Houston-based energy producer, (22% owned by Buffett’s Berkshire Hathaway ), climbed more than 2% after quarterly earnings surpassed analyst expectations. Occidental reported earnings of $1.18 per share amid strong oil production, higher than the consensus estimate of 84 cents per share, according to LSEG. Rivian — Shares of the electric vehicle maker shed more than 4% after analysts stayed neutral in their investment opinion, despite Rivian posting a smaller-than-expected loss in the latest quarter. Rivian also gave an optimistic forecast for the full year, increasing its production forecast by 2,000 units, to 54,000. Roblox — Shares jumped nearly 18% after third-quarter results beat Wall Street estimates. Roblox reported a loss of 45 cents per share on $839.5 million in revenue, while analysts polled by LSEG forecast a loss of 51 cents and revenue of $830 million. Toast — Shares of the restaurant-focused technology company slid 17% after Toast reported an unexpected loss for the third quarter. Boston-based Toast lost 9 cents per share, while analysts were expecting earnings of 10 cents per share, according to LSEG. Gross payment volume was fractionally below estimates, StreetAccount said. Robinhood — The trading platform fell more than 14% after missing revenue estimates in the third-quarter. Robinhood notched $467 million in the quarter, below analysts’ estimate of $478 million, according to LSEG. Warner Bros. Discovery — Stock in the media conglomerate plunged more than 16% after HBO and Food Network parent reported a wider-than-expected loss in the third-quarter. Warner Bros. posted an adjusted loss of 17 cents per share on $9.97 billion in revenue, while analysts polled by LSEG forecast a loss of 6 cents and revenue of $9.98 billion. Lyft , Uber — Lyft shares were down 0.6% at midday ahead of the ridesharing company’s quarterly results set for release Wednesday after the close. Uber was down by almost 1% after the company posted third-quarter results that missed sales and earnings estimates. EBay — The online marketplace warned of soft revenue in the current quarter and for the full year. In the third quarter, eBay beat the consensus forecast of analysts polled by LSEG for earnings per share, while revenue was in line with the consensus estimate. — CNBC’s Jesse Pound, Yun Li, Pia Singh, Alex Harring, Lisa Han, Tanaya Macheel and Sarah Min contributed reporting