In this article, we look at the 5 best mid cap stocks to invest in according to billionaies. If you want to see the full list and how we came up with the list, visit 10 Best Mid Cap Stocks to Invest In According to Billionaires.

5. NovaGold Resources Inc. (NYSEAMERICAN:NG)

Number of Billionaire Holdings: 12

Market Cap: $4.10 billion

NovaGold Resources Inc. (NYSEAMERICAN:NG) is one of the best mid cap stocks.

TheFly reported on April 8 that Morgan Stanley began coverage of NG, assigning an Overweight rating along with a price target of $13.80. The firm highlighted progress at the Donlin Gold project in Alaska, noting its high-grade profile and large scale as a key long-term growth driver. It also pointed to favorable market conditions for gold, supported by broader currency weakness, as a supportive backdrop for the asset’s development and valuation potential.

On April 1, NovaGold Resources Inc. (NYSEAMERICAN:NG) filed its first-quarter report for fiscal 2026 and provided an update on its Donlin Gold development project in Alaska. The company reported cash and term deposits of approximately $392.5 million as of February 28, 2026, alongside net operating cash expenditures of $20.8 million for the quarter, including funding for its share of project development and corporate expenses.

It also recorded a quarterly loss of $15.4 million, or $0.04 per share, reflecting increased spending tied to early feasibility work and ongoing administrative costs. During the period, NG advanced key development activities at Donlin Gold, including engineering partnerships and infrastructure planning, while continuing permitting and regulatory progress. The business also emphasized sustained engagement with local communities and stakeholders as part of its broader long-term project development strategy.

NovaGold Resources Inc. (NYSEAMERICAN:NG) is a precious metals company focused on the exploration and development of gold projects in North America. Its flagship asset is the Donlin Gold project in Alaska, one of the largest undeveloped gold resources globally, developed in partnership with Barrick Gold.

4. Klarna Group plc (NYSE:KLAR)

Number of Billionaire Holdings: 12

Market Cap: $4.95 billion

Klarna Group plc (NYSE:KLAR) is one of the best mid cap stocks to invest in.

TheFly reported on April 9 that KLAR and the Douglas Group, a European premium beauty retailer, expanded their existing partnership into Italy and Spain. The agreement extends Klarna’s checkout services to customers in both countries, allowing shoppers to use flexible payment options at the point of purchase. This includes the ability to divide payments into interest-free installments, improving accessibility for consumers in Southern Europe. The expansion builds on prior collaboration across other European markets and further increases Klarna’s presence in the region’s retail payment ecosystem.

Earlier on April 1, Klarna Group plc (NYSE:KLAR) completed a new capital efficiency arrangement structured as a Significant Risk Transfer transaction involving €1.7 billion in euro-denominated loans. The deal was arranged with a consortium led by Värde Partners under a three-year agreement. This marks the company’s sixth transaction of this type and is intended to improve capital deployment efficiency across its global operations. By transferring a portion of credit risk, KLAR frees up balance sheet capacity to support continued business expansion and lending activity, strengthening its ability to scale while maintaining more effective use of capital resources.

Klarna Group plc (NYSE:KLAR) is a global fintech company offering payment and shopping solutions. It specializes in “buy now, pay later” services, enabling consumers to split payments or defer purchases while helping merchants boost sales through flexible checkout options.

3. Ondas Inc. (NASDAQ:ONDS)

Number of Billionaire Holdings: 13

Market Cap: $4.40 billion

Ondas Inc. (NASDAQ:ONDS) is also one of the best mid cap stocks on this list.

TheFly reported on April 7 that ONDS announced that its subsidiary Sentrycs secured multiple contracts worth millions of dollars from federal, state, and local public safety agencies to support airspace security during the 2026 FIFA World Cup.

The deployment will focus on protecting stadiums, fan zones, and related event areas across matches hosted in 16 cities throughout the United States, Canada, and Mexico. Sentrycs’ counter-unmanned aircraft systems will be used at most venues to detect, track, and manage unauthorized drone activity. The technology is designed for non-disruptive operation in crowded environments, supporting large-scale security needs while maintaining regulatory compliance and operational safety throughout the tournament.

Separately, a day earlier on April 6, Ondas Inc. (NASDAQ:ONDS) reported that its subsidiary 4M Defense secured a competitive contract for a large-scale demining initiative along a strategic border area. The program is expected to generate more than $50 million in near-term and follow-on orders, adding to a previously announced $30 million demining project. The initiative strengthens the company’s involvement in next-generation border infrastructure and security solutions. ONDS also noted additional long-term opportunities that could expand into hundreds of millions of dollars in future system deployments, highlighting potential growth in broader border protection and infrastructure modernization programs over time.

Ondas Inc. (NASDAQ:ONDS) is a technology company focused on providing autonomous drone and private wireless solutions. It develops industrial drone platforms and secure communication networks used in sectors such as defense, public safety, transportation, and critical infrastructure.

2. Avantor, Inc. (NYSE:AVTR) 

Number of Billionaire Holdings: 13

Market Cap: $5.35 billion

Avantor, Inc. (NYSE:AVTR) is among the best mid cap stocks.

TheFly reported on April 6 that Evercore ISI maintained its In Line rating on AVTR while reducing its price target from $10 to $8.50. The adjustment was made as part of the firm’s broader preview of the medical technology and life sciences tools sector ahead of first-quarter results.

Earlier on April 1, Avantor, Inc. (NYSE:AVTR) announced that its Executive Vice President and Chief Financial Officer, R. Brent Jones, will be departing the company on or before June 24, 2026. In response, the company has begun the process of identifying a permanent successor to fill the CFO role. To maintain continuity during the transition period, Steve Eck, Senior Vice President and Chief Accounting Officer, will step in as interim CFO once Jones leaves.

Eck has been with Avantor since 2019, overseeing financial reporting and internal control functions, and brings extensive prior experience from senior finance positions at several organizations, including CSS Industries, Fidelity National Information Systems, General Electric, and Deloitte & Touche. The company emphasized its focus on ensuring an orderly leadership transition while maintaining stability in its financial operations and reporting structure until a new CFO is appointed.

Avantor, Inc. (NYSE:AVTR) is a global provider of mission-critical products and services to the life sciences, advanced technologies, and applied materials industries. It supplies lab materials, chemicals, and solutions that support research, development, and biopharmaceutical manufacturing.

1. StubHub Holdings, Inc. (NYSE:STUB)

Number of Billionaire Holdings: 17

Market Cap: $2.20 billion

StubHub Holdings, Inc. (NYSE:STUB) is among the best mid-cap stocks to invest in.

TheFly reported on April 9 that Guggenheim analyst Curry Baker noted that STUB reportedly agreed to a $10 million settlement with the Federal Trade Commission over allegations related to failure to clearly disclose full ticket prices, including mandatory fees. The firm suggested this development could have positive implications for Live Nation’s ongoing FTC case. It highlighted that Live Nation has taken steps to curb secondary ticketing practices and has supported consumer-focused pricing reforms such as all-in pricing and resale limits. Guggenheim also emphasized that Live Nation is increasingly viewed as more compliant relative to peers and may be in a stronger position to resolve its regulatory matters within the year.

Separately, earlier on March 26, StubHub Holdings, Inc. (NYSE:STUB) and Vivenu announced a partnership enabling event organizers on Vivenu’s platform to directly access StubHub’s global audience of over 125 million users across more than 200 countries. The integration is active immediately, requires no exclusivity, and is available at no cost.

It connects Vivenu’s ticketing system with STUB’s marketplace, allowing organizers to list tickets on StubHub directly from their dashboard. Ticket sales made through StubHub are automatically synchronized across channels, ensuring inventory updates in real time. Under the arrangement, STUB manages payment processing, customer service, and ticket delivery for transactions completed through its platform.

StubHub Holdings is a digital marketplace for buying and selling tickets to live events such as concerts, sports, and theater. It connects fans with resellers, providing pricing transparency and access to tickets for in-demand events globally.

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