Ten mid-cap companies from diverse sectors stood out on Monday, outperforming the lackluster performance of major indices, thanks to a flurry of corporate developments that sparked investor appetite.

While the firms boasted between 5 and 14 percent gains, the Dow Jones rose by only 0.32 percent, while the S&P 500 and the tech-heavy Nasdaq each inched up by 0.09 percent and 0.02 percent, respectively.

In this article, we list the names of the top-performing stocks and detail the reasons behind their gains.

To come up with the list, we considered only the stocks with a $2 billion market capitalization and $5 million in trading volume.

10. Oklo Inc. (NYSE:OKLO)

Shares of Oklo rallied for a seventh consecutive day on Monday, adding 5.33 percent to close at $39.73 apiece as investors continued to load up on shares following its strong earnings performance in the first quarter.

Last week, Oklo Inc. (NYSE:OKLO) reported trimming its net loss by 59.16 percent to $9.8 million from the $24.02 million registered in the same period last year, despite incurring a 142-percent jump in operating expenses, worth $17.9 million versus $7.37 million year-on-year.

Further adding to the sentiment was the appointment of new chief technology officer, Pat Schweiger, who boasts decades of experience and expertise in power engineering.

Prior to joining Oklo Inc. (NYSE:OKLO), Schweiger also served as chief engineer at SPARC at Commonwealth Fusion Systems and senior vice president and vice president for TerraPower.

“Pat’s decades of experience and expertise in power engineering will be a tremendous asset to Oklo as we move toward the commercialization of our advanced nuclear technologies,” said Oklo Inc. (NYSE:OKLO) co-founder and CEO Jacob DeWitte.

9. ZIM Integrated Shipping Services Ltd. (NYSE:ZIM)

ZIM Integrated grew its share prices by 5.67 percent on Monday to end at $19.37 apiece following an impressive earnings performance in the past quarter of the year.

In its earnings release, ZIM Integrated Shipping Services Ltd. (NYSE:ZIM) said that net income attributable to shareholders soared by 227 percent to $295.3 million from $90.3 million in the same period last year, as revenues increased by 28 percent to $2 billion from $1.56 billion year-on-year.

ZIM Integrated Shipping Services Ltd. (NYSE:ZIM), however, posted a cautiously optimistic outlook for the rest of the year, reaffirming its target adjusted EBITDA of $1.6 billion to $2.2 billion, and adjusted EBIT worth $350 million to $950 million.

“The operating environment is highly uncertain, driven by a range of factors impacting global trade and economic expectations,” said President and CEO Eli Glickman.

But “we are confident that we have built a resilient business and will continue to benefit from the strategic investment in our fleet with larger, more modern, cost-effective capacity, approximately 40 percent of which is LNG-fueled. Supported by our lower cost base, we believe ZIM is well positioned to drive profitable growth over the long term,” he added.

8. Moderna, Inc. (NASDAQ:MRNA)

Moderna Inc. grew its share prices by 6.15 percent on Monday to finish at $26.39 apiece as investor sentiment was buoyed by the Department of Health and Human Services’ pledge not to upend the US vaccine system.

Additionally, investors are in a wait-and-see mode for a planned “massive framework” for the US vaccine industry.

Details have yet to be publicized, but the plan is being overseen by the Food and Drug Administration.

Investors were hopeful that any initiative could benefit both end-consumers and vaccine makers such as Moderna, Inc. (NASDAQ:MRNA), which found success with its own COVID-19 shots.

In the first quarter of the year, Moderna, Inc. (NASDAQ:MRNA) narrowed its net loss by 17.4 percent to $971 million from $1.17 billion in the same period last year. Revenues declined by 35 percent to $108 million from $167 million in the same period last year due to lower vaccination rates, coupled with the continued normalization of COVID into a seasonal commercial market.

Looking ahead, Moderna, Inc. (NASDAQ:MRNA) is targeting to book revenues between $1.5 billion and $2.5 billion.

7. TXNM Energy, Inc. (NYSE:TXNM)

TXNM Energy saw its share prices rally by 6.98 percent to close at $56.57 apiece following news that it is set to be acquired by one of the largest investment management companies, Blackstone Inc., for $11.5 billion.

In a statement, Blackstone said its infrastructure arm inked an agreement with TXNM Energy, Inc. (NYSE:TXNM) to acquire its shares for $61.25 apiece.

The price represented an 8-percent upside from its closing price on Monday, as well as a 23-percent premium to its 30-day volume-weighted average price (VWAP) as of March 5, 2025, the day prior to an article reporting a developing acquisition for TXNM Energy.

According to Blackstone, the transaction will be funded through equity and assumption of existing debt, and no incremental debt will be issued as a result of the transaction.

The transaction is expected to be closed in the second half of 2026, subject to regulatory approvals and customary closing conditions.

6. D-Wave Quantum Inc. (NYSE:QBTS)

D-Wave Quantum saw its share prices rise by 7.35 percent on Monday to finish at $13.15 apiece.

Based on its historical price data, D-Wave Quantum Inc. (NYSE:QBTS) appears to be trading sideways as investors await fresh catalysts to further boost buying appetite.

In the first quarter of the year, D-Wave Quantum Inc. (NYSE:QBTS) reported that revenues expanded by 508 percent to $15 million from $2.465 million in the same period last year, primarily driven by the sale of a quantum computing system during the period.

Despite remaining in the red, the higher figures helped narrow the company’s net loss by 69 percent to $5.421 million from $17.312 million year-on-year.

“The first quarter of 2025 was arguably the most significant in D-Wave’s history, especially in terms of our unique ability to deliver quantum value today to our customers and the scientific community,” said D-Wave Quantum Inc. (NYSE:QBTS) CEO Alan Baratz.

5. CoreWeave, Inc. (NASDAQ:CRWV)

CoreWeave rallied for a second day on Monday, adding 7.83 percent to close at $86.59 apiece following plans to raise another $1.5 billion in fresh funds through the offer of senior notes due 2030.

In a statement on Monday, CoreWeave, Inc. (NASDAQ:CRWV) said that the offer will be guaranteed on a senior unsecured basis by its wholly-owned subsidiary, CoreWeave Cash Management LLC.

It said proceeds will be used to fund general corporate purposes, including repayment of outstanding debt, and to pay fees, costs, and expenses in connection with the offering of the notes.

Following the announcement, CoreWeave, Inc. (NASDAQ:CRWV) received a “B+” issuer credit rating from Moody’s Ratings.

In recent news, CoreWeave, Inc. (NASDAQ:CRWV) said in a regulatory filing that it clinched an additional $4 billion deal with OpenAI through 2029.

The deal was on top of the $11.9-billion deal already in place, under which CoreWeave, Inc. (NASDAQ:CRWV) provides OpenAI cloud computing capacity.

4. UnitedHealth Group Incorporated (NYSE:UNH)

Shares of UnitedHealth Group rallied by 8.21 percent on Monday to close at $315.89 apiece as investors resumed bargain-hunting after the company hit a new 52-week low late last week, weighed down by reports that it is being investigated over alleged fraudulent activities in its Medicare payouts.

On Thursday, the Wall Street Journal reported that the Department of Justice (DOJ) is investigating UnitedHealth Group Incorporated (NYSE:UNH) over its Medicare billing practices, sending its share prices falling to its lowest level of $248.88.

According to the report, the investigation has been ongoing since the middle of 2024 to look into whether the company fraudulently inflated patient diagnoses to rake in higher payouts from Medicare.

Meanwhile, UnitedHealth Group Incorporated (NYSE:UNH) called the report “deeply irresponsible, as even it admits that the ‘exact nature of the potential criminal allegations is unclear.’”

It said that it had not been formally notified of any criminal investigation but said that it “stands by the integrity of [its] Medicare Advantage program.”

Shareholder law firms have launched their own investigations into potential securities fraud alleged in the pending suit.

3. BGC Group, Inc. (NASDAQ:BGC)

BGC Group grew its share prices by 8.9 percent on Monday to end at $10.03 apiece following news that it agreed to repurchase more than 16.4 million common shares beneficially owned by US Secretary of Commerce and former chairman and CEO, Howard Lutnick.

In a statement, BGC Group, Inc. (NASDAQ:BGC) said it agreed to buy back the shares at a price of $9.2082 apiece for a total of $151 million, in furtherance of Lutnick’s US government ethics agreement.

“Repurchasing more than 16.4 million of our shares demonstrates our commitment to shareholder capital return,” said BGC Group, Inc. (NASDAQ:BGC) CFO Jason Hauf “Given our record first quarter results and anticipated strong cash flow generation this year, we believe buying back our shares in this highly efficient manner is a great use of our capital that delivers strong value creation to our shareholders.”

The transaction divested Lutnick’s ownership, voting, and economic interests in the company.

2. Hesai Group (NASDAQ:HSAI)

Hesai Group rallied by 10.07 percent on Monday to end at $19.46 apiece as investor sentiment was boosted by news that it officially filed its intention to list publicly on the Hong Kong Stock Exchange.

According to a report by Bloomberg, Hesai Group (NASDAQ:HSAI) is now working with banks on a potential offering that could take place this year.

While the recent filing does not directly affect shares of the company, the move will provide a safety net to investors, particularly for ADR holders, through continued capital market access and trading liquidity.

Hesai Group (NASDAQ:HSAI) is among the Chinese companies feared at risk of potential delisting from US stock exchanges amid geopolitical tensions between the US and China.

Additionally, Hesai Group (NASDAQ:HSAI) was added to a Pentagon blacklist in 2023 over alleged military ties, an allegation which it earlier debunked.

1. Sable Offshore Corp. (NYSE:SOC)

Sable Offshore jumped by 14.41 percent on Monday to finish at $33.02 apiece following news that it officially restarted oil production at the Santa Ynez Unit (SYU) in offshore California, 10 years after it was shut down due to regulatory hurdles and pipeline leaks.

In a statement, Sable Offshore Corp. (NYSE:SOC) said that it initiated last week the flow of oil production from six wells on Platform Harmony of the SYU to the Las Flores Canyon at a rate of ~6,000 barrels of oil per day.

“Sable has been testing wells on Platform Harmony throughout May 2025, and the well tests have performed consistently stronger than they did at the time of shut-in on May 19, 2015, when the SYU produced approximately 45,000 barrels of oil equivalent per day,” it said.

Sable Offshore Corp. (NYSE:SOC) expects to initiate production from the additional 44 wells on Platform Heritage and the additional 26 wells on Platform Hondo in July 2025 and August 2025, respectively.

Following the news, the company doubled its production guidance for the second half of 2025, now between 40,000 to 50,000 boe/pd from the previous 20,000 to 25,000 boe/pd.

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