In this article, we deep dive into the 5 Stocks Racking Up Monster Gains. For a deeper discussion and an extended list, please see 10 Stocks Investors Are Chasing Right Now.

5. AST SpaceMobile Inc. (NASDAQ:ASTS)

AST SpaceMobile rallied for a second day on Monday, surging 21.44 percent to close at $86.77 apiece, as investor sentiment was boosted by reports that it is partnering with the Rakuten Group for the development of a Japanese version of satellite internet service similar to Starlink.

A report by Nikkei said that Japan-based Rakuten Group is partnering with AST SpaceMobile Inc. (NASDAQ:ASTS) for a possible $1 billion joint venture, under which the parties would buy and operate satellites to establish a direct-to-mobile service.

The report said that Japan’s coverage is targeted for next year.

Additionally, AST SpaceMobile Inc. (NASDAQ:ASTS) rallied following confirmation that its next-generation BlueBirds 8, 9, and 10 are now fully operational in orbit, with its manufacturing pipeline now advancing all the way through BlueBird 37.

“BlueBirds 8, 9, and 10 are in orbit and operational; 11, 12, and 13 are next. Satellites in production through BlueBird 37,” the company said in a social media post.

Last week, AST SpaceMobile Inc. (NASDAQ:ASTS) said that it is scheduled to launch BlueBirds 11, 12, and 13 in the first half of August in line with its efforts to expand its space-based cellular broadband network designed to provide voice, data, video, directly to standard, unmodified smartphones everywhere.

“BlueBirds 11, 12, and 13 build on the momentum of our recent constellation and represent another important milestone as we prepare for commercial service. The progression from BlueBirds 8, 9, and 10 to this next mission, together with the continued production and assembly of satellites through BlueBird 37, reflects the strength of our manufacturing capabilities and our ability to steadily expand the network while we work to connect the unconnected and under-connected around the world,” President and CEO Scott Wisniewski said.

4. Iridium Communications Inc. (NASDAQ:IRDM)

Iridium Communications soared to a nearly three-year high on Monday, as investors gobbled up shares following news that it is set to merge with Rocket Lab Corp. for $8 billion.

The two parties announced the signing of a definitive agreement on the same day, under which Rocket Lab will acquire all issued and outstanding shares of Iridium Communications Inc. (NASDAQ:IRDM) in a combination of cash and stock.

Under the terms of the agreement, Iridium Communications Inc. (NASDAQ:IRDM) shareholders are set to receive $27 in cash and shares of Rocket Lab, calculated pursuant to an exchange ratio for each share of Iridium common stock outstanding at the closing, which, if combined, would equate to $54 apiece.

Complete details on the exchange ratio calculation will be in the transaction agreement, which will be filed with the Securities and Exchange Commission.

The transaction is expected to be completed in the middle of 2027, subject to regulatory approvals, including approval of Iridium Communications Inc. (NASDAQ:IRDM) stockholders, among others.

The transaction has been unanimously approved by the boards of directors of both companies.

3. FuelCell Energy Inc. (NASDAQ:FCEL)

FuelCell saw its share prices increase by 24.17 percent on Monday to close at $29.80 apiece, as investors loaded up on its shares ahead of its expansion plan in South Korea.

This followed news on the same day that FuelCell Energy Inc. (NASDAQ:FCEL) was able to raise $49 million in fresh funds from a financing package from the Export-Import Bank of the United States (EXIM), proceeds of which will be used to support the development of a fuel cell energy project for Gyeonggi Green Energy (GGE) in South Korea.

FuelCell Energy Inc. (NASDAQ:FCEL) is set to develop five 2.8 MW fuel cell energy blocks for GGE, boosting its capacity by an additional 14 MW.

At present, GGE boasts of 60 MW of installed capacity, making it among the largest fuel cell developers in the world.

FuelCell Energy Inc. (NASDAQ:FCEL) said that the second tranche of the total amount is expected to be released in October 2026, subject to customary closing conditions.

EXIM structured the financing under its loan guarantee program and arranged with Private Export Funding Corporation (PEFCO), supporting the export of American clean energy technology to international markets. It builds upon FuelCell Energy Inc.’s (NASDAQ:FCEL) prior EXIM-supported financing completed in 2024 and 2025 and reflects continued support for the company’s export of US-manufactured clean energy technology.

2. SELLAS Life Sciences Group Inc. (NASDAQ:SLS)

SELLAS Life Sciences extended its winning streak to an 8th straight session on Monday to soar to a new record high, as investors resumed buying positions after hinting at a potential takeover.

In intra-day trading, the stock rocketed to a record high of $15.67 before trimming gains to end the session just up by 24.70 percent at $15.45 apiece.

In a regulatory filing last week, Sellas Life Sciences Group Inc. (NASDAQ:SLS) announced changes to its employment and severance agreements with three of its executive members, namely President and CEO Angelos Stergiou, Chief Financial Officer John Burns, and Chief Development Officer Dragan Cicic, under which they would receive lump-sum payment benefits in case of a “change of control.”

Sellas Life Sciences Group Inc. (NASDAQ:SLS) noted that Burns and Cicic are set to receive lump-sum payments equal to 15 months of their base salary, target bonus for the year of termination, and immediate vesting of unvested shares, among others, in case they are not absorbed by new company owners.

Investors believed that the changes were in preparation for a potential takeover, as the company nears the release of the phase 3 results of its therapy candidate for acute myeloid leukemia (AML).

Last month, Sellas Life Sciences Group Inc. (NASDAQ:SLS) said that it would provide updates to the late-stage study as soon as it reaches the study’s 80th patient death, a pre-determined event it deemed enough to analyze results on whether or not its Galinpepimut-S (GPS) treatment candidate made a meaningful improvement to patients versus those in the placebo group.

As of last month, the company had 78th patient deaths.

1. Ouster Inc. (NASDAQ:OUST)

Ouster saw its share prices climb to a new four-year high on Monday, as investors positioned their portfolios amid the growing importance of digital lidar solutions to AI development.

In intra-day trading, the stock jumped to a record high of $54.49 before trimming gains to end the session just up by 28.68 percent at $54.07 apiece.

In a statement, Ouster Inc. (NASDAQ:OUST) said that it joined forces with AIM for the integration of its Rev8 native color digital lidar into the AIM AI platform to further advance the perception capabilities of its next-generation automated machinery with precise 3D structural data, color point clouds, and industrial-grade imagery to safely accelerate autonomous operations in complex, unstructured environments.

For AIM, the partnership aims to result in faster edge-computing, streamlined sensor fusion, and significantly enhanced safety and object-classification capabilities in real-time, high-dust industrial workflows.

“As heavy industry, mining, and logistics rapidly transition toward autonomous operations, highly reliable, high-resolution 3D perception is paramount. We are thrilled to deepen our relationship with AIM Intelligent Machines as they scale their AI-powered fleets for heavy equipment and explore the transformative potential of our new Rev8 family,” Ouster Inc. (NASDAQ:OUST) Chief Revenue Officer Cyrille Jacquemet said.

“By embedding our native color digital lidar into their intelligent platforms, AIM can redefine what automated machines can see, interpret, and achieve safely at scale,” he noted.

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