Comcast $(CMCSA)$: The company announced plans to split into two through a tax-free spin-off of NBCUniversal and Sky; shares jumped premarket.

Rocket Lab (RKLB), Iridium Communications $(IRDM)$: Rocket Lab agreed to buy Iridium in a cash-and-stock deal that would give it control over a satellite fleet and access to wireless resources it could use to compete with SpaceX. Shares in Rocket Lab jumped 10% premarket, while Iridium's soared about 22%.

British American Tobacco (UK: BATS): The tobacco giant and maker of Dunhill cigarettes saw its London-listed shares drop more than 1% after it announced plans to cut 5,500 jobs and outsource a further 3,500 roles.

Palantir Technologies (PLTR): Shares of the data-analytics company climbed premarket, further recovering from a multi-day losing streak driven by fears about the sustainability of the artificial-intelligence rally. Other stocks tied to the AI trade, such as Nvidia Corp (NVDA) and Intel Corp $(INTC)$, also notched premarket gains.

Samsung Electronics (KR: 005930), SK Hynix (KR: 000660): Shares in the South Korean chipmakers ended the day lower, but pared losses after they committed massive new investments in building chip production facilities in the country.

Verizon Communications $(VZ)$: BT, a London-listed telecommunications operator, said it would form a joint venture with the U.S. telecommunications provider.

Ipsen (FR: IPN): The French drugmaker said it agreed to buy U.S.-based clinical stage biopharmaceutical company Kartos Therapeutics to add to its pipeline of cancer medicines. Its shares rose.