DUOL
Duolingo, Inc. Class A Common Stock
stock NASDAQ

Respectfully, the “but Duolingo is using AI too!” argument is exactly what the market priced in during the August bloodbath.
Timeline for anyone who missed it:
- Aug 6: DUOL smashes earnings → closes at $390 (+12 % that day)
- Aug 7: OpenAI GPT-5 livestream. They literally prompt “build me a French-learning app” and in <15 minutes GPT-5 spits out a fully interactive web app with gamified vocab (Snake but you collect cheese), pronunciation, streaks, daily quizzes — i.e. a pocket Duolingo made by AI from scratch, live on stream.
- Next week: DUOL drops 18 % in a straight line, wiping out the entire post-earnings gain and then some. Analysts (Goldman, Citi, etc.) explicitly called out the GPT-5 demo as the catalyst.
Duolingo can (and does) use OpenAI’s APIs, but that’s not a moat when the same APIs let any random dev, teacher, or even a kid with a good prompt build a tailored competitor in an afternoon for $0. The demo made that terrifyingly concrete.
The stock has stabilized a bit since, but it’s still ~35–40 % off the May highs for a reason. The market isn’t punishing Duolingo for being slow on AI — it’s punishing them for the sudden realization that AI makes their core product extremely easy to replicate.
Happy to be proven wrong if they find a new durable edge, but “we use AI too” isn’t it when GPT-5 just showed the world how to clone the entire experience in one livestream.

FIG, DUOL, ENPH

I’d love to hear your bull case on ADBE and DUOL. Those two have been my best performing shorts of 2025

High Cap: $NVDA | $META | $BABA | $AMD | $UNH | $LLY | $GOOG
Mid Cap: $NBIS | $SOFI | $HOOD | $NIO | $IREN
Small Cap: $DUOL | $HIMS | $OSCR | $EOSE | $LMND | $ASTS | $ZETA | $RKLB

AXON - down 15%
DUOL - down 15%
I don’t regret AXON, and I keep buying it slowly. DUOL on the other hand…

You’ve got a pretty concentrated growth/AI tilt on top of broad US and global ETFs, so your overall risk is heavily tied to large-cap tech even though VT and XLU add some diversification. One way to sanity-check your predictions is to look at what portion of your portfolio is in broad indexes (VOO/VT/QQQ) versus single names (NVDA, AAPL, META, DUOL, ANET) and ask how you’d feel if the AI/mega-cap theme underperforms for a few years. VT slowly becoming your top holding will naturally reduce single-stock risk over time, while XLU is a small but useful ballast if rates stay lower. If you want to visualize how much of your portfolio is really in US tech versus other sectors and regions, a tool like [WizardFolio.com](http://WizardFolio.com) or any ETF look-through site can help you see the underlying exposures more clearly.