Platform Margins Update + A New MCP/GPT Tool for Transcript Research | PA Dispatch No. 13
A quick view of this week’s shifts in platforms, valuations, and AI adoption. Numbers, context, and curated reads you can use.
I’ve been looking at one of my favorite charts that compares EBITDA margins (as a % of GBV, on a TTM basis) against incremental margins and the spread tells an interesting story.
Actual vs. Incremental: The Chart Worth Staring At
Booking. sits at the top on both dimensions: 5.3% actual EBITDA margin and a 7.9% incremental margin. That incremental figure is the highest in the group. When a business is adding margin on new revenue at nearly 8 cents on the dollar, that’s a compounding story. The gap between where they are today and where they can go is a function of volume, not structural change (pending AI impact).
Uber presents a more interesting case. At 4.5% actual and 7.3% incremental, the gap is large (nearly 300 basis points) which implies meaningful operating leverage as the business scales. Uber has been on a deliberate path toward EBITDA discipline after years of growth-at-all-costs, and the incremental margin profile here suggests that path is working. Every dollar of incremental GBV is being converted at a much higher rate than the blended base. The delivery and freight businesses still compress the consolidated number, but mobility’s underlying economics are pulling the incremental rate up materially.
Airbnb is the puzzle. At 4.7% actual EBITDA margin, the absolute number isn’t embarrassing, but the 3.0% incremental margin is the second-lowest in the group. For a marketplace with virtually no physical supply, no employees operating the assets, and a brand that doesn’t require nearly the performance marketing spend of an OTA, a 3% incremental margin figure is hard to explain away. There’s a real question about whether the platform has hit an S-curve on core alternative accommodations and whether experiences and services can pick up the slack. Management flagged that 2025 was a heavier investment year and telegraphed margin expansion in 2026.
The 2.9% club Expedia, Instacart, and Lyft share the same actual margin but diverge on incrementals. Expedia converts at 6.5%, Instacart at 5.4%, and Lyft at 6.1%. Those incremental figures are meaningfully above the base, which suggests all three still have operating leverage to harvest.
DoorDash has the lowest actual margin at 2.7%, with a 4.0% incremental. The company just announced it plans to ramp 2026 tech and autonomy spend. That investment cycle will likely compress near-term incrementals further. The thesis there is a multi-year one (international expansion, restaurant tech, autonomous delivery) and is real, but they require patience before the margin profile reflects it.
The broader takeaway: actual margins tell you where a business is today; incremental margins tell you the direction and velocity. A business with a low actual margin but high incremental (Uber, Expedia) is on a convergence path. A business with a high actual margin but low incremental (Airbnb) is worth watching for signs of structural compression. Booking’s combination of both is what makes it the benchmark.
New Tool: Query All Platform Aeronaut Transcripts via CustomGPT
I’ve built a CustomGPT on ChatGPT that lets subscribers search and query across the full archive of Platform Aeronaut transcript records. Rather than scrolling back through issues to find what a specific exec said about AV unit economics or margin guidance, you can now ask directly.
A few things to know:
Authentication currently only works on desktop so if you’re on mobile, bookmark it and come back when you’re at a computer
It’s early, and I want to improve it based on how people actually use it
Feedback is genuinely useful if a query returns something off, or there’s a category of questions it handles particularly well, I want to hear it
The goal is to make the transcript archive as queryable as possible. There’s a lot of signal buried in what management teams say quarter over quarter, and pattern-matching across that manually is time-consuming. This should help.
Give it a spin and let me know what you think.
Performance & Valuation Snapshot
Note: Email renders these as images, click through for interactive filters or view on Platform Aeronaut.
What I Read This Week
Congress probes AI pricing at major travel platforms: The House Oversight chair asked Uber, Lyft, Expedia, Booking.com, and Instacart to explain whether they use AI-driven “surveillance pricing” and to provide documents by March 19
OTA stocks jump after report that OpenAI is backing away from direct checkout in ChatGPT: Expedia, Booking, and TripAdvisor rose after a Reuters-reported market reaction to The Information’s report that OpenAI is scaling back direct-booking ambitions inside ChatGPT
GetYourGuide names a new CPO as the experiences market keeps scaling: GetYourGuide hired Rob Rekrutiak and said it surpassed €1 billion in revenue with 33 million experiences booked in 2025, reinforcing the size of the category.
Kroger leans harder into partner-led last mile: Kroger’s new CEO said the retailer aims for e-commerce profitability next year by using stores as fulfillment hubs and leaning on Instacart, DoorDash, and Uber Eats for delivery
Navan launches an AI assistant for unmanaged business travelers: Navan Edge targets travelers outside employer-managed programs with AI trip planning, itinerary management, and disruption support.
Agentic AI in travel is running into a trust problem: A fresh industry roundtable featuring Booking.com, Google, Sabre, and Skyscanner framed the current bottleneck as consumer trust and operational readiness, not just model capability.
Transcript Highlights
Instacart (CART) Morgan Stanley TMT Conference
Gen AI productivity gains that include a 40% higher output per engineer on average, top 10% engineers at 80% output improvement, and end-to-end project velocity up to 4x in some initiatives.
Agentic interfaces and AI-driven discovery are expected to create incremental small-basket use cases while preserving large-basket weekly habits.
Company prioritized four execution areas for 2026: marketplace growth, enterprise expansion, advertising scale, and AI/agent development.
Roblox (RBLX) Morgan Stanley TMT Conference
Views AI as a tailwind and is investing aggressively in gaming-specific AI to accelerate creator productivity.
Roblox is building interoperable tooling that allows creators to use both internal and third-party AI capabilities to produce content.
Not dependent on hits, noting over 14 million experiences and that roughly two-thirds of engagement time in 2025 occurred outside the top 10 titles. The company reported that experiences outside the top 10 grew bookings ~55% year-on-year and pointed to strong Q4 bookings growth (63%) without a new viral hit.
Expedia (EXPE) Morgan Stanley TMT Conference
Expedia reports roughly 2/3 of traffic as direct and is prioritizing diversification of acquisition channels including early AI agent partnerships.
Views AI as an opportunity to diversify acquisition channels and improve product personalization, citing roughly 2/3 of traffic as direct and over 50% self-service. The stated approach combines experimentation with AI-enabled product improvements, self-service scale, and supplier onboarding enhancements
Expedia reported a 10% increase in listed properties in Q4 and plans continued onboarding of chains, independents, and Vrbo inventory across 2026 and beyond.
The information presented in this newsletter is the opinion of the author and does not reflect the view of any other person or entity, including Altimeter Capital Management, LP (”Altimeter”). The information provided is believed to be from reliable sources but no liability is accepted for any inaccuracies. This is for informational purposes and should not be construed as investment advice or an investment recommendation. Past performance is no guarantee of future performance. Altimeter is an investment adviser registered with the U.S. Securities and Exchange Commission. Registration does not imply a certain level of skill or training. Altimeter and its clients trade in public securities and have made and/or may make investments in or investment decisions relating to the companies referenced herein. The views expressed herein are those of the author and not of Altimeter or its clients, which reserve the right to make investment decisions or engage in trading activity that would be (or could be construed as) consistent and/or inconsistent with the views expressed herein.
This post and the information presented are intended for informational purposes only. The views expressed herein are the author’s alone and do not constitute an offer to sell, or a recommendation to purchase, or a solicitation of an offer to buy, any security, nor a recommendation for any investment product or service. While certain information contained herein has been obtained from sources believed to be reliable, neither the author nor any of his employers or their affiliates have independently verified this information, and its accuracy and completeness cannot be guaranteed. Accordingly, no representation or warranty, express or implied, is made as to, and no reliance should be placed on, the fairness, accuracy, timeliness or completeness of this information. The author and all employers and their affiliated persons assume no liability for this information and no obligation to update the information or analysis contained herein in the future.






Love the page / thoughtful pieces you put out! Curious why you spend time creating these given transcript features now exist on platforms like Rogo and, to some extent, FactSet