Although U.S. stocks closed lower on Monday, there were a few notable insider trades.

When insiders purchase shares, it indicates their confidence in the company's prospects or that they view the stock as a bargain. Either way, this signals an opportunity to go long on the stock. Insider purchases should not be taken as the only indicator for making an investment or trading decision. At best, it can lend conviction to a buying decision.

Below is a look at a few recent notable insider purchases. For more, check out Benzinga's insider transactions platform.

Hallador Energy

The Trade: Hallador Energy Company ( HNRG ) Director Charles Ray Wesley IV acquired a total of 46,100 shares an average price of $5.21. To acquire these shares, it cost around $240,136.

What's Happening: On March 25, Hallador Energy ( HNRG ) announced the appointment of Marjorie Hargrave as Chief Financial Officer.

What Hallador Energy Does: Hallador Energy Co ( HNRG ) is a coal mining company with operations in Indiana, USA, and it is part of the electric power generation industry.

Pacific Premier Bancorp

The Trade: Pacific Premier Bancorp, Inc. ( PPBI ) Director Barbara Polsky acquired a total of 1,200 shares at an average price of $23.92. To acquire these shares, it cost around $28,704.

What's Happening: On Jan. 29, Pacific Premier Bancorp ( PPBI ) posted upbeat quarterly earnings.

What Pacific Premier Bancorp Does: Pacific Premier Bancorp Inc ( PPBI ) through its subsidiaries, provides banking products and services. It offers cash management, electronic banking services, credit facilities, and retirement accounts, among others.

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OmniAb

The Trade: OmniAb, Inc. ( OABI ) President and CEO Matthew W Foehr bought a total of 225,000 shares at an average price of $5.19. To acquire these shares, it cost around $1.17 million.

What's Happening: On March 20, OmniAb ( OABI ) posted a narrower-than-expected quarterly loss.

What OmniAb Does: OmniAb Inc ( OABI ) offers therapeutic antibody discovery technologies. Its focus is to enable the rapid development of therapeutics by pushing the frontiers of drug discovery technologies.

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