The Week’s Biggest Funding Rounds: Fleetio And Mercury Nab Massive Rounds
A big week for big-money rounds. Seven startups locked up massive rounds of $100 million or more. That includes two cybersecurity firms and two companies in the transportation space.

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This is a weekly feature that runs down the week’s top 10 announced funding rounds in the U.S. Check out the biggest funding rounds of last week here.
A big week for big-money rounds. Seven startups locked up massive rounds of $100 million or more. That includes two cybersecurity firms and two companies in the transportation space.
1. Fleetio, $450M, fleet management: Fleet optimization software platform developer Fleetio locked up a $450 million round to finance the acquisition of maintenance authorization platform Auto Integrate. The new round was co-led by existing Fleetio investor Elephant and new investor Goldman Sachs Alternatives’ growth equity branch, and values the Bermingham, Alabama-based company at more than $1.5 billion. The new company will service more than 8 million vehicles and process more than 13 million repair orders per year. Founded in 2011, the company has raised $620 million, per Crunchbase.
2. Mercury, $300M, fintech: Fintech startup Mercury raised a massive $300 million Series C led by new investor Sequoia Capital. The new round includes primary and secondary funding and values the company at $3.5 billion — more than double its previous Series B valuation of $1.6 billion in 2021. The San Francisco-based company offers bank accounts integrated with various financial tools businesses need. Founded in 2017, the company has raised $452 million, per Crunchbase.
3. Island, $250M, cybersecurity: Dallas-based enterprise browser developer Island raised a $250 million Series E at a $4.8 billion valuation. The new round was led by Coatue Management, with several existing investors participating in the round, per the company. The new valuation represents a 60% jump from last April when Island raised a $175 million Series D at a $3 billion valuation, also led by Coatue. The company has approximately 500 employees, with more than 200 in product development and engineering, and over 450 customers. The deal comes just about a week after Google parent Alphabet announced its intention to buy cloud security unicorn Wiz for $32 billion — the biggest ever M&A exit for a VC-backed company. That deal likely will stoke investor interest in cyber, which already saw venture funding increase last year compared to 2023. Island itself is no stranger to big-money rounds. In October 2023, it raised a $100 million Series C led by Prysm Capital that valued the company at $1.5 billion. In March 2022, it announced a $115 million Series B at a $1.3 billion valuation led by Insight Partners — minting it a unicorn just seven weeks after launching. Founded in 2020, the company has raised $810 million, per Crunchbase.
4. Aura, $140M, cybersecurity: Cybersecurity has seen its fair share of big rounds this year. Just a couple of weeks ago, Boston-based cybersecurity startup Cybereason announced a $120 million investment led by SoftBank, SoftBank Vision Fund 2 and Liberty Strategic Capital. This week a large round goes to another Boston-based cyber firm, as Aura raised $140 million in equity and debt at a valuation of $1.6 billion in a Series G led by Ten Eleven Ventures and Madrone Capital Partners. Unlike most cyber startups that raise big, Aura is more on the consumer side, developing a tool for family cybersecurity that provides device security, scam and fraud protection, child safety and online predator alerts, and identity theft protection. Founded in 2017, the company has raised nearly $663 million, per Crunchbase.
5. Supira Medical, $120M, medical device: Los Gatos, California-based Supira Medical, a developer of percutaneous ventricular assist devices, locked up a $120 million Series E led by new investors Novo Holdings and Qatar Investment Authority. Founded in 2012, the company has raised nearly $241 million, per Crunchbase.
6. Nexthop AI, $110M, artificial intelligence: Artificial intelligence infrastructure provider Nexthop AI raised a massive $110 million round led by Lightspeed Venture Partners. The Santa Clara, California-based startup builds custom networking solutions for the hyperscalers, including networking hardware designed to each customer’s specifications and a choice of a network operating system with the company’s own AI. Lightspeed Venture Partners has been busy the past month-plus. In February, the VC giant co-led satellite platform developer K2 Space’s $110 million Series B with Altimeter Capital. It also participated in a slew of big rounds, including autonomous surface vessels maker Saronic’s $600 million Series C, medical document startup Abridge’s $250 million round, and application security startup Semgrep’s $100 million Series D. This month, it led Anthropic’s huge $3.5 billion funding round that valued the startup at $61.5 billion.
7. Also, $105M, transportation: Palo Alto, California-based electric micromobility company Also raised a $105 million round led by Eclipse Ventures as it launched from stealth.
8. Heartflow, $98M, health care: Heartflow, a developer of a noninvasive coronary care platform, raised approximately $98 million through the sale of convertible notes. Investors included Fidelity Management & Research Co. Founded in 2010, the Mountain View, California-based company has raised nearly $891 million, per Crunchbase.
9. Character Biosciences, $93M, biotech: Jersey City, New Jersey-based Character Biosciences, a biotech using genomics, clinical data and AI-driven modeling to drive drug development, raised a $93 million Series B co-led by new investors aMoon Fund and Luma Group. Founded in 2018, the company has raised $120 million, per Crunchbase.
10. Omaha Productions, $80M, media: Los Angeles-based Omaha Productions has raised a new financing round from Patrick Whitesell Holding. Omaha is Peyton Manning‘s entertainment company. The new round values the company at $800 million.
Big global deals
The biggest raise this week came from across the pond.
- U.K.-based Level, an application that provides loans, funding, financial, tax returns, liquidity, legal advice and lending services, raised a venture round worth nearly $136 million.
Methodology
We tracked the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the seven-day period of March 22 to March 28. Although most announced rounds are represented in the database, there could be a small time lag as some rounds are reported late in the week.