After a strong August, markets moved mostly sideways in September ↔️
In this recap, we look at how the major indexes performed in September, how our portfolios did compared to the market, which stocks were our biggest winners and losers, and the changes we made during the month.
Dive into our full September Recap below 👇
📢 Our Best Buys for October are coming early next week — don't miss it 🎯
What Moved the Markets in September
September markets moved mostly sideways, but there was a lot of news, especially around AI. The biggest theme of the month was the risk of AI. Anthropic CEO Dario Amodei called for companies to slow the development of their most advanced AI models. Sam Altman and Elon Musk agreed that AI needs stronger controls.
Nvidia responded with its new Open Agent Safety Platform, designed to keep AI agents under control and stop them from accessing systems they shouldn’t. The company also increased its share buyback to $150 billion.
President Donald Trump hosted leaders from many of the world’s largest AI companies and officially changed the government’s wording from Artificial Intelligence to Super Intelligence.
Anthropic launched several new Claude models and filed its IPO prospectus, with a potential valuation above $2 trillion. OpenAI launched GPT-6 Astra and Dots, always-on AI agents that can connect to apps, complete tasks and keep working for users.
Meta launched Muse, its personal AI agent, and connected it with Shopify, PayPal and Plaid to help users shop, pay and manage purchases with AI. It also launched Muse for small businesses and the new Meta Enterprise Platform for companies. Microsoft introduced a major Copilot upgrade built around Home, Code and Autopilot.
Alphabet launched Gemini 4 Argon, its most advanced AI model yet, with big improvements in coding and cybersecurity. Synopsys signed a $1 billion+ deal with Amazon for custom chip design and partnered with OpenAI to build GPT-Synopsys, an AI model made specifically for chip design.
Apple unveiled the iPhone Duo, its first foldable iPhone and one of the biggest changes to the iPhone in years.
There was plenty of movement in individual stocks as well. Lululemon dropped sharply after disappointing earnings, and FICO fell almost 50% during the month after Fannie Mae and Freddie Mac opened the door to VantageScore 4.0, putting pressure on FICO’s moat and pricing power.
Uber cut around 3,300 jobs and is putting more money into rides, delivery and autonomous vehicles. Uber and Wayve launched autonomous rides in London, and Waymo is preparing robotaxi launches in Tokyo and Singapore.
Nu expanded beyond Latin America into the U.S., launching checking, savings and credit products. It also introduced Nu Global, a multi-currency financial platform, and is in early talks to acquire UK digital bank Monzo.
Novo Nordisk rebranded to Novo and presented its post-Wegovy growth plan, targeting more than five new blockbuster launches by 2030 and over DKK 150 billion in risk-adjusted pipeline sales by 2035. Novo also partnered with Anthropic to bring Claude into drug discovery and R&D.
September also brought important management changes. Adobe named Anil Chakravarthy as its next CEO, replacing Shantanu Narayen. MongoDB CEO CJ Desai left to lead Meta’s new enterprise AI business, with Dev Ittycheria stepping in as interim CEO.
Salesforce agreed to acquire Listen Labs, an AI platform that uses agents to run customer research and analyze feedback. Grab acquired a controlling stake in BNPL platform Atome.
Finally, AMD acquired World Labs, the spatial intelligence company founded by Fei-Fei Li, and reached a $1 trillion market cap for the first time.
How did the markets perform in September? Here's how the three major indexes ended the month:
S&P 500: -0.5% 📉 (+11.8% YTD)
Nasdaq: +1.9% 📈 (+15.6% YTD)
Dow Jones: -4.3% 📉 (+5.9% YTD)
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Portfolio Performance: How Did We Do?
How did our portfolios perform in September?
We compare our performance with the S&P 500, Nasdaq, and Dow Jones, look at our biggest winners and losers, and walk you through the portfolio changes we made during September.
Dive into the full recap below 👇
Available exclusively for our paid subscribers ✨