Check out the companies making the biggest moves in premarket trading:

Shake Shack – The fast food chain saw its stock gain nearly 4% 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 acquired a 6.6% stake including swaps.

Charles Schwab — Stock in the brokerage firm added 2.4% in premarket trading. Raymond James said in a note on Monday that Schwab’s core banking business remains strong, which could help the stock gain as much as 30%. On Friday, the company said total client assets increased 1% from March to April to $7.63 billion.

Magellan Midstream Partners, Oneok — Shares of Magellan Midstream Partners soared 15.5% following the announcement that pipeline operator Oneok is acquiring the company for about $18.8 billion. Oneok shares dropped 5.5%.

H&R Block, Intuit — The tax preparers sank 9.3% and 4.3%, respectively, following a Wall Street Journal report on the Biden Administration’s potential creation of a government-run online tax filing program. The IRS is due to release the report this week, the paper said. The agency has been looking into it as part of the Inflation Reduction Act.

SoFi Technologies — The stock sank nearly 6% in the premarket following a downgrade by Wedbush to underperform from neutral. The Wall Street firm said SoFi’s fee income may be reaching a tipping point and it may need to raise capital this year to support growth.

Albemarle — Shares rose 2.7% following an upgrade to outperform by Baird. The firm said the lithium company can be a leader in both the near- and long-term.

Dupont De Nemours— Shares added 2.7% in premarket trading after Deutsche Bank upgraded the chemical company to buy from hold. The Wall Street firm said the stock was trading at a 50% discount to its peers.

— CNBC’s Yun Li, Alex Harring and Brian Evans contributed reporting.