The 10 Biggest Rounds Of October: OpenAI’s Massive Deal Dwarfs All Others

This is a monthly feature that runs down the month’s top 10 funding rounds in the U.S. Check out September’s biggest rounds here.

OpenAI led the way last month and it really wasn’t even close. However, there were lots of other big raises — as a startup had to raise more than $200 million to make October’s list as investors were very willing to open their checkbooks for megadeals.

1. OpenAI, $6.6B, artificial intelligence: OpenAI announced its long-awaited raise of $6.6 billion at a post-money valuation of $157 billion led by Thrive Capital. The new round makes the ChatGPT creator one of the most valuable private companies in the world and also included investment from the likes of Altimeter Capital, Fidelity, Khosla Ventures, Microsoft, Nvidia, SoftBank and Abu Dhabi-based MGX. It also was reported SoftBank’s Vision Fund would invest $500 million in the round. The new round comes just as the company is facing myriad issues, including an exodus of higher-up employees and a restructuring change to switch it from a nonprofit to a for-profit benefit corporation and to give co-founder Sam Altman equity in the company. The funding structure seems to take those factors into account, as it came in the form of convertible notes and reportedly allows for investors to ask for their money back if the change is not completed within two years and removes the cap on returns for investors. The new round is bigger than the $6 billion round Elon Musk’s generative AI startup, xAI, officially announced in May, which up to this point was the largest round raised this year.

2. Pacific Fusion, $900M, energy: Another huge AI-related round. Pacific Fusion, a startup attempting to create a nuclear fusion-based energy source, raised more than $900 million in a Series A led by General Catalyst. The funding does depend on the company hitting certain milestones — which were not spelled out. The round further illustrates investors’ appetite for energy sources that can meet AI’s immense power needs.

3. (tied) Crusoe Energy Systems, $500M, energy: Back in 2022, the Denver-based company was helping power Bitcoin mining by harnessing natural gas that is typically burned during oil extraction and putting it toward powering the data centers needed for mining — raising a $350 million Series C equity round led by G2 Venture Partners, at $1.75 billion valuation in the process. Well, Crusoe has now turned its energy to AI — literally. The company is a so-called “neocloud” — a data center firm providing outsourced cloud computing for those looking to build AI. That business plan was enough for Crusoe to reportedly lock up a $500 million round led by Founders Fund at a $3 billion valuation. Founded in 2018, the company has raised $1.2 billion, per Crunchbase.

3. (tied) Poolside, $500M, artificial intelligence: Poolside closed a $500 million Series B led by Bain Capital Ventures. The new round valued the startup at $3 billion, Bloomberg reported. The startup builds artificial intelligence software for programmers. Poolside is just one of a handful of big deals recently in the AI coding space. In August, San Francisco-based Magic, which also develops AI models to write software, raised a $320 million round, and AI-powered coding assistant Codeium closed a $150 million Series C. Poolside has raised $626 million since being founded in May 2023.

3. (tied) X-energy, $500M, energy: Rockville, Maryland-based X-energy raised a Series C-1 of approximately $500 million, anchored by Amazon. The company is developing advanced small modular nuclear reactors for clean energy generation. Amazon and X-energy are collaborating to bring more than 5 gigawatts of new power projects online across the United States by 2039. Founded in 2009, X-energy has raised more than $785 million, per Crunchbase.

6. Form Energy, $405M, renewable energy: Form Energy, a renewable energy company developing and commercializing multiday energy storage systems, raised a $405 million Series F led by T. Rowe Price. Long-duration energy storage has proven to be a tough nut to crack, but Form has been able to get some commercial traction as it looks to ramp up manufacturing operations and commercial deployments of its iron-air battery systems. The Somerville, Massachusetts-based company, founded in 2017, has raised a total of $1.5 billion in a mix of equity and grants, per Crunchbase.

7. (tied) Kailera Therapeutics, $400M, biotech: Yet another big biotech raise last month, as Kailera Therapeutics announced its launch with a $400 million Series A financing co-led by Atlas Venture, Bain Capital Life Sciences and RTW Investments. The new Boston-based company is developing several clinical-stage injectable and oral therapies to help with chronic weight management.

7. (tied) Lightmatter, $400M, data centers: Lightmatter, a startup that uses light to link chips together and to do calculations for the deep learning necessary for AI, locked up a $400 million Series D led by new investor T. Rowe Price at a $4.4 billion valuation. The new round nearly quadruples its previous valuation of $1.2 billion in December after a $155 million raise led by GV — which along with Fidelity Management and Research Co. also participated in the new round. As Big Tech pours hundreds of billions of dollars into new AI data centers, Lightmatter is trying to solve the problems around energy consumption and scalability of those new centers. The company’s tech uses silicon photonics that can speed up processes while also using less power. Although the idea of using light in computing isn’t new, creating the components has historically been challenging. Founded in 2017, Lightmatter has raised $850 million, per the company. Lightmatter’s was not the only large raise by a photonic startup last month. Xscape Photonics — a New York-based startup also using photonics technology to address the energy, performance and scalability challenges of AI data centers — raised a $44 million Series A led by IAG Capital Partners with investment from the likes of Cisco Investments and Nvidia.

9. Splitero, $300M, fintech: Part of the beauty of being a homeowner is having equity in that home. Unfortunately, accessing that equity can sometimes be burdensome. San Diego-based Splitero offers homeowners another option to do just that and last month the startup locked up $300 million through a strategic investment from funds managed by Antarctica Capital to further that mission. Splitero offers homeowners a lump sum of cash in exchange for a share of their home’s future value. Founded in 2021, the company has raised nearly $318 million, per Crunchbase.

10. Seaport Therapeutics, $225M, biotech: Seaport Therapeutics isn’t new to this list. In April, the Boston-based startup launched with a $100 million Series A co-led by Arch Venture Partners and Sofinnova Investments. The company is back with a $225 million Series B led by General Atlantic. The biotech company focuses on medicines for depression, anxiety and other neuropsychiatric disorders. Seaport will use the new money to advance its clinical-stage pipeline of medicines.

Big global deals

The biggest deal outside the U.S. came from across the Pacific.

• China-based GDS International, a developer and operator of data centers, raised $1 billion from institutional private-equity investors.

Methodology

We tracked the largest rounds in the Crunchbase database that were raised by U.S.-based companies for the month of October 2024. Although most announced rounds are represented in the database, there could be a small time lag as some rounds are reported late in the month.

Illustration: Dom Guzman