The Week’s Biggest Funding Rounds: OpenAI Easily Tops Massive Week

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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.

This was a week right out of the free-spending days of 2021. Huge rounds were abundant — led by the biggest of them all as OpenAI’s massive $40 billion investment was finally announced.

1. OpenAI, $40B, artificial intelligence: Of course the big news of the week was the $40 billion investment for OpenAI led by SoftBank. The deal is the biggest venture investment ever. Per details of the deal, SoftBank will build a syndicate of co-investors to provide $10 billion of the total, while it expects to fund the other $30 billion, with  $10 billion of that through debt. The deal also is partially contingent upon conditions of OpenAI’s restructuring of its for-profit subsidiary. If that occurs, OpenAI will have a post-money valuation of $300 billion.

2. Silicon Ranch, $500M, energy: Nashville, Tennessee-based Silicon Ranch raised $500 million from European infrastructure investor AIP Management. The big investment is likely a bet on the U.S.’ increasing electricity demands. Silicon Ranch — which operates solar and battery projects — has been on this list before. Back in 2022, the company raised $775 million in equity capital led by Manulife Investment Management. Founded in 2011, the energy company has raised more than $2 billion, according to Crunchbase data.

3. Plaid, $575M, fintech: Plaid raised a massive $575 million round led by Franklin Templeton at a $6.1 billion valuation. The San Francisco-based company plans to use the cash to pay employee tax withholding obligations related to share conversion and to offer some liquidity to employees via a tender offer. Plaid, which connects user bank accounts to fintech apps, had a planned $5.3 billion sale to Visa scrapped back in 2021 following regulatory issues.

4. Runway, $308M, artificial intelligence: New York-based Runway raised $308 million in a new round at about double its valuation from less than two years ago. The new round — led by General Atlantic — values the AI video startup at more than $3 billion, per reports. In June 2023, the company raised a $141 million extension to its December 2022 $50 million Series C. Runway makes software that lets users create videos using text prompts or images. Earlier in the week, Runway unveiled its new AI model, Gen-4, that allows users to create videos with consistent characters and backgrounds. Last fall, the company signed a deal with production company LionsGate to create a customized video-generation model. The startup plans to use the fresh cash to develop AI focusing on its film and animation studio. Founded in 2018, it has raised more than $540 million, per Crunchbase.

5. AIRNA, $155M, biotech: Cambridge, Massachusetts-based AIRNA, a biotech startup developing RNA editing therapeutics to help with both rare and common conditions, closed a $155 million Series B led by Forbion Capital Partners and Venrock Healthcare Capital Partners. The new cash will go toward launching a phase trial for AIRNA’s drug candidate for alpha-1 antitrypsin deficiency and help it develop its pipeline of RNA editing therapeutics. Founded in 2021, the company has raised $245 million, per Crunchbase.

6. (tied) Atsena Therapeutics, $150M, biotech: Atsena Therapeutics, a gene therapy company focused on reversing or preventing blindness, closed a $150 million Series C led by Bain Capital’s Life Sciences arm. The money from the financing will be used to advance the Durham, North Carolina-based company’s treatment of X-linked retinoschisis, a genetic condition that is typically diagnosed in childhood and leads to blindness later in life. The proceeds will also support Atsena’s preclinical pipeline. Founded in 2019, the company has raised nearly $238 million, per Crunchbase.

6. (tied) SandboxAQ, $150M, quantum computing: Alphabet spinoff SandboxAQ — an AI and quantum computing startup — added another $150 million to its Series E from the likes Google and Nvidia. The add-on comes less than four months after the company announced it had raised a $300 million round at a $5.6 billion valuation. SandboxAQ is looking at the related effects of both AI and quantum — which is where the company gets “AQ” — to develop commercial products for telecom, financial services, health care, security and other computationally intensive sectors. The company already is working with a handful of customers on enterprise software and cybersecurity tools related to quantum computing. In March 2022, Alphabet officially spun off its 6-year-old quantum tech group — SandboxAQ — which emerged as its own company after closing a $500 million financing round and naming former Google CEO Eric Schmidt chairman. SandboxAQ has raised over $950 million, per the company.

8. Temporal Technologies, $146M, software: Seattle-based Temporal Technologies locked up a big $146 million Series C at a $1.7 billion valuation led by Tiger Global Management. The company helps other companies manage complex software applications and will use the new cash to develop cloud products and invest in research and development for artificial intelligence use. The company raised a $103 million Series B in February 2022 at a valuation of a little more than $1.5 billion, followed by $75 million in a Series “B-Prime.” Founded in 2019, Temporal has raised $350 million, per the company.

9. Neurona Therapeutics, $102M, biotech: Neurona Therapeutics, a South San Francisco-based clinical-stage biotech company developing regenerative cell therapies for disorders of the nervous system, raised a $102 million financing round. Investors included Fidelity Management & Research Co. Founded in 2008, the company has raised $426 million, per Crunchbase.

10. (tied) Cyberhaven, $100M, cybersecurity: Palo Alto, California-based Cyberhaven, an AI-powered data security startup, raised a $100 million Series D led by StepStone Group at a $1 billion valuation. Founded in 2016, Cyberhaven has raised $250 million, per the company.

10. (tied) Redpanda Data, $100M, data: Streaming data startup Redpanda Data raised a $100 million Series D led by GV at a $1 billion valuation. The San Francisco-based startup provides real-time streaming data services, helped by artificial intelligence and machine learning. Founded in 2019, Redpanda has raised nearly $265 million, per the company.

Big global deals

The biggest raise this week came from across the pond.

• Google spinoff Isomorphic Labs raised $600 million in its first external funding round as the company looks to apply artificial intelligence to the drug development process. The new round was led by Thrive Capital with participation from Google Ventures. The London-based AI company will receive follow-on capital from existing investor Alphabet.

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 29 to April 4. 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.

Illustration: Dom Guzman