The venture capital markets saw a burst of mega-deals and sectoral diversification last week, with biotech, AI, and energy infrastructure leading the charge. Investor optimism remained steady amid improving liquidity and continued strength in late-stage rounds, setting the tone for what could be another high-velocity week in global dealmaking.

Biotech Surges to the Top

The October 11–17 period was dominated by Kailera Therapeutics, which announced a $600 million Series B round led by Bain Capital Private Equity to advance its obesity-focused therapeutics toward Phase 3 trials. This represented the largest U.S.-based round of the week, signaling renewed enthusiasm for the biotech sector after several quarters of AI-heavy dominance.news.crunchbase​

Other healthcare-linked deals included Kardigan closing a $254 million Series B backed by T. Rowe Price, Sequoia Heritage, and Arch Venture Partners, while dermatology innovators VeraDermics and Pelage Pharmaceuticals raised $150 million and $120 million, respectively, to continue clinical trials for hair-regrowth and skin therapeutics.news.crunchbase​

Notably, Peptilogics ($78 million Series B2) continued biotech’s momentum with a specialized focus on infection prevention for surgical patients, and MD Integrations ($77 million) boosted telehealth infrastructure to meet growing remote-care demand.news.crunchbase​

Fintech, SaaS, and Aviation Land Mega-Rounds

Fintech remained active with Upgrade securing $165 million in a Series G round led by Neuberger Berman, targeting consumer lending and credit products ahead of a planned IPO. Payroll software leader Deel captured $300 million at a striking $17.3 billion valuation, citing over $1 billion in annual recurring revenue, while Vantaca raised an equal $300 million to scale homeowners association management systems.news.crunchbase​

In an intriguing diversification move, Bond, an aviation startup offering fractional jet ownership, grabbed $350 million in combined debt and equity funding from KKR and its founders, underlining investor interest in premium mobility and subscription travel models.news.crunchbase​

Billion-Dollar Bets in AI, Energy, and Space

In global venture activity through mid-October, mega-rounds reshaped frontier sectors. According to Intellizence data, Intercontinental Exchange (ICE), the parent company of the New York Stock Exchange, made a surprising entry into Web3 by investing up to $2 billion in prediction-market platform Polymarket—a signal of mainstream financial institutions embracing crypto-based market models.citybiz​

Meanwhile, Reflection AI secured an extraordinary $2 billion Series B at an $8 billion valuation, underscoring investor conviction in next-generation artificial intelligence platforms focused on large-scale model development and infrastructure expansion.citybiz​

Energy transition also drew significant capital: Base Power landed $1 billion in Series C funding to transform Texas’ fragile energy grid through a distributed home battery network—creating a scalable, virtual power plant ecosystem.citybiz​

In aerospace, Stoke Space raised $510 million (Series D) to advance fully reusable medium-lift rockets, representing continued confidence in private space infrastructure. Automation developer n8n rounded out the list with $180 million (Series C) at a $2.5 billion valuation, reflecting enterprise demand for customizable, self-hosted workflow automation tools.citybiz​

Together, these five deals accounted for over $5.6 billion in capital inflows, confirming that despite global caution and tighter due diligence, liquidity is increasingly flowing into long-duration innovation themes.citybiz​

Investor Sentiment and Market Outlook

The robust deal volume across sectors reflects broader market resilience. Quarter 3 data showed North American venture funding exceeding $63 billion, and analysts expect continued strength in late-stage financings through Q4 as public market sentiment improves and rate stability encourages growth-stage risk-taking.news.crunchbase+1​

Fundamentally, the AI-biotech-energy triad is emerging as the new golden intersection for venture capital. While valuations are holding at sustainable levels, liquidity trends suggest more strategic partnerships between institutional investors and specialized funds.

Looking ahead to the week of October 20–26, the VC community expects:

• Multiple follow-on rounds for health and enterprise-AI startups.

• A potential uptick in fintech IPO filings amid favorable exit windows.

• Renewed fund announcements by mid-tier venture firms before year-end closes.

• Possible cooling in early-stage crypto activity offset by institutional Web3 infrastructure deals.

As capital continues to gravitate toward transformative sectors like clean energy, prediction markets, and next-gen AI, venture markets appear poised for another dynamic week.

In essence, last week’s activity confirmed that venture capital is pivoting strategically—from volume to conviction. With over $10 billion flowing across technology, biotech, and sustainability domains in just a few days, investors are signaling that innovation-led growth remains fully in motion heading into late October 2025.mordorintelligence+3​