Top 10 Startup and Tech Funding News – September 11, 2025

It’s Thursday, September 11, 2025, and we’re back with the top startup and tech funding news stories shaping today’s global landscape. From billion-dollar bets in quantum computing to fresh seed rounds fueling the next wave of AI, healthtech, and customer support, investors stayed active across every stage and geography.

Today’s coverage highlights a mix of late-stage heavyweights and promising newcomers. PsiQuantum dominated the headlines with a record-breaking $1 billion Series E to push fault-tolerant quantum computing closer to reality, while Perplexity AI locked in $200 million at a staggering $20 billion valuation as it continues to challenge Google in search. Diana Health raised $55 million to scale its women’s health clinics, Koi secured $48 million to rethink endpoint security, and Motion snapped up $38 million to grow its AI-powered “work suite” for SMBs.

Funding Highlights

• PsiQuantum secured a historic $1 billion Series E, pushing its valuation to $7 billion and strengthening its position in quantum computing.

• Perplexity AI hit a $20 billion valuation with a $200 million raise, reinforcing investor appetite for conversational AI search.

• Diana Health brought in $55 million in Series C funding to expand its maternal and women’s health clinics.

• Koi raised $48 million across seed and Series A to tackle security gaps created by unmanaged enterprise software.

• Motion captured $38 million Series C, bringing total funding to $75 million as it builds an AI “agentic” suite for SMBs.

• Additional notable rounds included Unmind ($26M growth financing for workplace mental health), Sophont ($9.22M seed for multimodal medical AI), Quack ($7M seed for proactive AI support), Eloquent AI ($7.4M seed for financial services automation), and Meela ($3.5M seed for AI companionship for seniors).

Investor Activity

Some of the world’s most influential investors doubled down today, including BlackRock, Nvidia, Temasek, Baillie Gifford, Battery Ventures, Scale Venture Partners, and Bain Capital Ventures. Strategic participation from corporates and deep involvement from top-tier VCs highlighted confidence in both the capital-intensive sectors like quantum and AI, and the early-stage startups reshaping healthtech, security, and customer experience.

The spread once again revealed a familiar pattern: mega-rounds powering frontier tech alongside robust seed activity in verticals that matter most to the next decade. Together, these financings show that conviction in ambitious founders building the future remains strong.

Here’s the full breakdown. Until tomorrow, have a great evening.

PsiQuantum Grabs $1B in Series E Funding to Scale Fault-Tolerant Quantum Computing

PsiQuantum, a California-based quantum computing startup, has secured a colossal $1 billion Series E funding round to accelerate the development of its photonic quantum computers. The raise values PsiQuantum at about $7 billion, more than double its valuation from 2021, reflecting strong investor confidence in its approach to building fault-tolerant, million-qubit quantum machines.

The new capital will enable PsiQuantum to expand its large-scale quantum production sites, deploy prototype systems for design validation, and continue refining its silicon photonic chips in partnership with industry leaders. This significant investment underscores the growing momentum in quantum tech as PsiQuantum aims to move quantum computing out of the lab and into practical, enterprise-scale use.

Funding Details:

• Startup: PsiQuantum

• Investors: BlackRock (lead), Nvidia (NVentures), Temasek, Baillie Gifford, Morgan Stanley’s Counterpoint Global, Qatar Investment Authority; with existing backers Blackbird and Third Point Ventures

• Amount Raised: $1 billion

• Total Raised: Nearly $2 billion (to date)

• Funding Stage: Series E

• Funding Date: September 11, 2025

Perplexity AI Secures $200M in Funding at $20B Valuation to Scale Conversational Search Platform

Perplexity AI, the San Francisco-based AI search startup challenging Google with its conversational answer engine, has raised $200 million in fresh funding at a whopping $20 billion valuation. This late-stage capital injection comes only two months after Perplexity’s previous round, bringing its total funding to about $1.5 billion since its 2022 founding.

Perplexity’s platform blends real-time web search with an AI chatbot interface that provides answers with source citations, attracting over 30 million users and a rapidly growing revenue base. The new funding will fuel further expansion of its AI capabilities and user reach as Perplexity doubles down on its bid to reinvent search. The company did not disclose specific new investors for this round; a prior financing in July was led by Accel.

Funding Details:

• Startup: Perplexity AI

• Investors: Not disclosed (Accel led an earlier round; existing backers include marquee Silicon Valley VCs)

• Amount Raised: $200 million

• Total Raised: ~$1.5 billion

• Funding Stage: Undisclosed (Late-stage round)

• Funding Date: September 10, 2025

Diana Health Raises $55M in Series C Funding for Women’s Health Clinics

New York-based Diana Health, a healthcare startup co-designing women’s health and maternity care programs with hospitals, has raised $55 million in a Series C round to grow its network of modern maternal health clinics. The funding, led by HealthQuest Capital with participation from prior investors Norwest Venture Partners, .406 Ventures, LRVHealth, and AlleyCorp, will support Diana Health in scaling its physical clinic footprint and enhancing its digital health platform.

Founded in 2019 and led by CEO Kate Condliffe, Diana Health partners with hospitals to improve outcomes in labor and delivery units and women’s health centers, focusing on team-based care and whole-person wellness. This latest round brings Diana Health’s total reported funding to about $100 million, underscoring strong investor commitment to innovating maternal care.

Funding Details:

• Startup: Diana Health

• Investors: HealthQuest Capital (lead), Norwest Venture Partners, .406 Ventures, LRVHealth, AlleyCorp

• Amount Raised: $55 million

• Total Raised: $100 million (reported)

• Funding Stage: Series C

• Funding Date: September 11, 2025

Koi Lands $48M in Funding to Reinvent Endpoint Security with AI

Koi, a Washington, D.C.-based cybersecurity startup, announced $48 million in funding across its combined seed and Series A rounds to redefine endpoint security for modern software environments. The financing includes a $38 million Series A led by Battery Ventures, Team8, Picture Capital, and NFX, with additional participation from Cerca Partners.

Founded in 2024 by veterans of Israel’s elite Unit 8200 cyber unit, Koi is tackling the blind spots in enterprise security created by self-installed, unmanaged software. Its platform adds a centralized “security layer” on company endpoints, providing visibility into unvetted apps, real-time risk analysis powered by an AI engine, and automated policy enforcement to block threats before they spread.

With over half a million endpoints already protected, Koi’s fresh capital will accelerate product development and global customer reach in the fight against emerging software supply chain risks.

Funding Details:

• Startup: Koi

• Investors: Battery Ventures, Team8, Picture Capital, NFX (co-leads); with participation from Cerca Partners

• Amount Raised: $48 million (Seed + Series A)

• Total Raised: $48 million

• Funding Stage: Seed & Series A

• Funding Date: September 10, 2025

Motion Snaps Up $38M in Series C Funding to Build an AI “Work Suite” for SMBs

Y Combinator-backed Motion has raised $38 million in a Series C round, part of a recent funding surge that brings its total capital to $75 million and values the company at $550 million. The San Francisco-based startup offers an “agentic work suite” – a platform of AI-powered digital workers that autonomously handle tasks in sales, marketing, project management, and more for small and mid-sized businesses.

After six years of development, Motion’s product has evolved from a simple productivity tool into a comprehensive AI agent platform that automates routine business workflows without costly custom integration. The oversubscribed Series C was led by Scale Venture Partners (with Scale’s Stacey Bishop joining the board) and saw strong support from insiders HOF Capital, 468 Capital, SignalFire, and Y Combinator, plus new investors like Valor Equity Partners and Fellows Fund.

Motion will use the new funding to expand operations, boost R&D on its AI “employees,” and continue its rapid growth as a go-to AI work solution for over 10,000 SMBs.

Funding Details:

• Startup: Motion

• Investors: Scale Venture Partners (lead); HOF Capital, 468 Capital, SignalFire, Y Combinator, Valor Equity Partners, Fellows Fund, Leonis Capital, and others

• Amount Raised: $38 million

• Total Raised: $75 million

• Funding Stage: Series C

• Funding Date: September 11, 2025

Unmind Secures $26M in Funding to Expand AI-Powered Mental Health Platform

London-based Unmind, a workplace mental health platform, has received $26 million in growth funding to scale its AI-driven employee well-being solution. The capital comes in the form of growth financing from Trinity Capital, following Unmind’s recent Series C round, and brings the company’s total funds raised to over $100 million since inception.

Unmind’s platform provides a comprehensive mental health toolkit for organizations – from self-guided wellness programs and coaching to therapy and crisis support – all coordinated by its AI assistant “Nova” that personalizes care for each user. Trusted by global companies like Uber and Disney, Unmind plans to use the new funding to accelerate product innovation (particularly around Nova), expand its global reach, and ensure more employees worldwide have access to proactive mental health resources.

Funding Details:

• Startup: Unmind

• Investors: Trinity Capital (lead growth investor)

• Amount Raised: $26 million

• Total Raised: $100 million+

• Funding Stage: Growth Capital (Venture Debt)

• Funding Date: September 11, 2025