Check out the companies making headlines in midday trading. Warner Bros. Discovery — Shares dropped 9.9% after the media conglomerate posted disappointing fourth-quarter results and failed to give 2024 free cash flow guidance. Warner Bros. Discovery reported a loss of 16 cents per share on revenue of $10.28 billion. Analysts polled by LSEG, formerly known as Refinitiv, had expected a per-share loss of 7 cents on revenue of $10.35 billion. Block — Block shares surged more than 16% after the payments company reported a surprise quarterly profit and offered up strong guidance on earnings before interest, taxes, depreciation and amortization for the first quarter and full year. DraftKings — The sports betting stock added 1% following an upgrade to overweight from equal weight by Barclays. The firm said the stock was at an attractive entry point following a recent pullback. Rivian — The electric vehicle stock sank 12% and hit a 52-week low, a day after tumbling nearly 26%. Rivian issued a 2024 production forecast on Thursday that came below estimates and reported a wider-than-expected fourth-quarter loss of $1.36 per share. On Friday, UBS downgraded shares to sell from buy and slashed its price target to $8 from $24. Bloomin’ Brands — The restaurant company rose nearly 3% after reporting a beat on adjusted earnings per share in the fourth quarter, per FactSet. Restaurant margins also were better than expected. Booking Holdings — The stock declined 10.1% after the online travel booking company issued weaker-than-expected gross booking and EBITDA guidance for the first quarter, overshadowing better-than-expected quarterly results. Nio — The U.S.-traded shares of the Chinese EV company fell 7.7% following a downgrade from JPMorgan . The investment firm said Nio could see its sales volume grow more slowly than expected, citing the lack of new models as a concern. Live Nation Entertainment — Shares of the entertainment platform added about 2% after Live Nation reported a fourth-quarter revenue of $5.84 billion, higher than the $4.79 billion analysts polled by LSEG had expected. Carvana — Shares of the used car marketplace jumped 32.1% after the struggling company posted its first-ever annual profit. Carvana guided for first-quarter adjusted EBITDA “significantly above” $100 million. Following the results, William Blair upgraded Carvana to outperform from market perform, and Raymond James upgraded it to market perform from underperform. MercadoLibre — Shares dropped about 10% after the e-commerce platform posted flat year-over-year earnings for the fourth quarter. Operating income also missed estimates. Penumbra — The stock fell 9.3%. JPMorgan downgraded the medical device company to neutral from overweight, noting “Penumbra will be in the penalty box until it can prove to investors that it is able to guide to levels it can consistently beat and raise off of.” Nextdoor Holdings — Shares jumped more than 16% after the company’s preliminary fourth-quarter revenue came in stronger than expected. Nextdoor also announced a $150 million increase to its share repurchase program. Co-founder Nirav Tolia also will return as CEO. Insulet — Shares slipped 6.5% after the company reported a disappointing revenue forecast for the first quarter. Insulet forecasts revenue will grow 17% to 20% annually, while analysts surveyed by FactSet called for 24.3%. EOG Resources — The oil company slid 3.9% after issuing weak guidance for the current quarter and full year. EOG posted in-line earnings and a revenue beat in the fourth quarter. — CNBC’s Alex Harring, Samantha Subin, Brian Evans, Lisa Kailai Han, Jesse Pound, Michelle Fox and Sarah Min contributed reporting.