Amkor, KLA Corporation, Monolithic Power Systems, Potbelly, and Bally's Shares Plummet, What You Need To Know

What Happened?

A number of stocks fell in the afternoon session after stocks gave back some of the gains from the previous day as the White House clarified the tariffs on imports from China would add up to 145%, while the baseline 10% tariffs remained in place for most countries. This reminded markets that the global trade environment remained volatile, limiting the potential for sustained gains. 

Also, President Trump said he was willing to accept pain in the short term, and was aware his policies could cause a recession, but he remained more mindful of a more severe case of economic depression (higher unemployment and prolonged downturn). For investors, this suggested that the administration could prioritize long-term structural shifts over near-term economic stability, further increasing policy-driven risk in the markets.

The stock market overreacts to news, and big price drops can present good opportunities to buy high-quality stocks.

Among others, following stocks were impacted:

• Semiconductor Manufacturing company Amkor (NASDAQ:AMKR) fell 12.1%. Is now the time to buy Amkor? Access our full analysis report here, it’s free.
• Semiconductor Manufacturing company KLA Corporation (NASDAQ:KLAC) fell 8%. Is now the time to buy KLA Corporation? Access our full analysis report here, it’s free.
• Analog Semiconductors company Monolithic Power Systems (NASDAQ:MPWR) fell 14.5%. Is now the time to buy Monolithic Power Systems? Access our full analysis report here, it’s free.
• Modern Fast Food company Potbelly (NASDAQ:PBPB) fell 5.5%. Is now the time to buy Potbelly? Access our full analysis report here, it’s free.
• Casino Operator company Bally's (NYSE:BALY) fell 10.8%. Is now the time to buy Bally's? Access our full analysis report here, it’s free.

Zooming In On Monolithic Power Systems (MPWR)

Monolithic Power Systems’s shares are extremely volatile and have had 32 moves greater than 5% over the last year. But moves this big are rare even for Monolithic Power Systems and indicate this news significantly impacted the market’s perception of the business.

The previous big move we wrote about was 6 days ago when the stock dropped 8.6% on the news that China imposed a 34% tariff on all U.S. imports amid escalating trade war tensions. This was especially rough for the US chipmakers because a big chunk of their business leans on demand out of China. The new tariffs not only threaten to erode profit margins but also risk reducing market share. Adding to the uncertainty, the Trump administration signaled the possibility of further regulatory action against the sector. Although semiconductor firms were notably excluded from the broad tariffs unveiled on April 2, 2025, their exclusion raised concerns that targeted restrictions could still be forthcoming.

Monolithic Power Systems is down 18% since the beginning of the year, and at $487 per share, it is trading 48.6% below its 52-week high of $947.16 from August 2024. Investors who bought $1,000 worth of Monolithic Power Systems’s shares 5 years ago would now be looking at an investment worth $2,833.

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