Stocks making the biggest moves midday: Shake Shack, Charles Schwab, Activision Blizzard and more

cnbc.com:

Check out the companies making headlines in midday trading.

Shake Shack — The fast food chain's stock jumped more than 6% after the Wall Street Journal reported that activist investor Engaged Capital is planning a proxy fight for three board seats at the company. Engaged Capital bought a 6.6% stake in Shake Shack, including swaps. The stock has rebounded more than 60% this year.

Magellan Midstream Partners, Oneok — Magellan Midstream Partners jumped 14.7% after Oneok agreed to acquire the company for about $18.8 billion. Oneok shares slid 7.7%.

Western Digital — Western Digital advanced 8% in midday trading. A Reuters report, citing two sources familiar with the matter, said the firm is ramping up merger talks with Kioxia Holdings, Japan's computer memory maker.

H&R Block, Intuit — Shares of the tax preparers dropped 3% and 2%, respectively, following reports of the potential creation of a government-run online tax filing program. The IRS is due to release the report this week, the Wall Street Journal reported. The agency has been looking into it as part of the Inflation Reduction Act.

Newmont — Shares of the gold miner added about 1% after it announced it would acquire Australian miner Newcrest. It is the third largest global deal so far this year, worth about $17.8 billion, according to Reuters.

Charles Schwab — The brokerage firm saw its shares climb more than 3% midday after Raymond James upgraded the stock and said it can rally almost 30%, as concerns about stability in U.S. banks have not affected Schwab's ability to attract new accounts and assets.

Microsoft, Activision Blizzard — The European Union on Monday approved Microsoft's proposed plan to buy gaming company Activision Blizzard for $69 billion. Activision