On CNBC's "Mad Money Lightning Round," Jim Cramer isn't thrilled with Palo Alto Networks, Inc. (NASDAQ:PANW), seemingly reversing his stance from April.

"Palo Alto's had three straight quarters where I'm worried," Cramer said. "All I can tell you is that I'm concerned."

On May 20, Palo Alto posted better-than-expected earnings for its third quarter. The stock is currently down 0.72% in pre-market, trading at $293.80 per share.

Cramer also recommended buying more Vertiv Holdings Co (NYSE:VRT). "I think the stock's terrific," he said.

On June 4, Vertiv said its board declared a quarterly cash dividend of 2.5 cents per share of Class A common stock, which will be payable on June 26, to shareholders of record of Class A common stock at the close of business on June 17.

Monday.com Ltd. (NASDAQ:MNDY) is "really good," Cramer said.

On May 15, Monday.com reported better-than-expected first-quarter financial results and issued revenue guidance above estimates. The company reported fiscal first-quarter 2024 revenue growth of 34% Y/Y to $216.9 million, beating the analyst consensus estimate of $210.4 million. The project management software company's adjusted EPS of 61 cents beat the analyst consensus estimate of 40 cents, according to data from Benzinga Pro.

The "Mad Money" host said NuScale Power Corporation (NYSE:SMR) is "very good company, but we got to be very aware that the nuclear power industry is many, many years before we'll see anything coming from that company, and it's going to lose money for a very long time."

On May 9, NuScale Power posted weaker-than-expected results for its first quarter.

Price Action:

• Vertiv shares fell 9.4% to settle at $88.00 on Thursday.
• Monday.com shares gained 3.5% to close at $223.59 on Thursday.
• NuScale Power fell 1.5% to close at $7.67 during Thursday's session.
• Palo Alto shares rose 0.2% to close at $295.93.

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