How I Invest · 5 min · Oct 26, 2026

OpenAI's open Codex strategy could win the application layer

MHMatthew Harris · Partner, Bain Capital Ventures

Matthew Harris says Codex accepting open-weight models is a shift toward an open application layer.

In this episode

1:58 Valuation discipline can make venture firms miss power-law winnersPro pick 5 min
17:35 AI labs may avoid competing with their biggest customers6 min
32:44 Anthropic's growth could support its reported $2 trillion valuation4 min
11:53 Bain's AI strategy centers on robotics and AI-native services6 min
8:51 AI market leadership can shift despite consensus investing3 min
27:59OpenAI's open Codex strategy could win the application layer5 min
52:38 Steady venture pacing helps limit cycle-driven risk5 min
39:48 AI agents could expand the market beyond human users3 min

“I think it's genius, actually, and I think they're still going to sell a lot of OpenAI tokens into codex”

MHMatthew Harrisat 30:42 · How I Invest

Takeaways

Codex lets users use open-weight models alongside OpenAI's.
OpenAI still expects to sell its own model tokens through Codex.
Harris sees platform ownership as a source of long-run advantage.

About this segment

Matthew Harris says Codex accepting open-weight models is a shift toward an open application layer. He compares owning that platform to Microsoft's advantage from controlling its operating system.

MH

Matthew Harris is a Partner at Bain Capital Ventures focused on financial services and technology.

David Weisburd, Host

From “Anthropic at $2 Trillion? The AI Bubble, and Why the Best Startups Always Look Overvalued”, Oct 26, 2026. Watch the full episode

Answers “How does OpenAI make money, and is it profitable?” See all 9 answers

Transcript

From the transcript How I Invest publishes with the episode.

28:11
What's the game theory between them and how they're looking at making these massive investments in compute? There are a lot of games being played. The original game, I think at both companies actually is about advancing the state of artificial intelligence and actually achieving generalized artificial intelligence. And that has become a little muddier as capitalism has kicked in, both for the individuals running these companies, more so in the case of Anthropic than OpenAI, but also just their competition itself and the human desire to win and not be second place.
28:51
And then these massive cap tables who have unambiguous goals, which are just to make as much money as possible. So I think the original game of being first to artificial general intelligence has been subsumed in a revenue and profits game, or at least complemented by it. And in doing so, the agendas have definitely shifted. OpenAI was more aggressive out of the gates in terms of being having audacity around funding.
29:17
They raced ahead. Anthropic caught up both with the product and now more recently with their ability to go get capacity. I think Elon is the best of the three at this at that particular game, both of building data centers specifically, but also about sort of just, you know, world building in people's minds and attracting vast capital to vast projects. So of the three, think on the data center game, I actually think the advantage sits with Elon.
29:46
OpenAI, Verseanthropic, They have a lot of business puts and takes right now. Think one of one one announcement here recently that I think was underreported on was OpenAI opening up model usage within Codex. So OpenAI wants to be a bunch of different things. They want to sell the most tokens and their most expensive models, but they also want to be the most popular, you know, coding tool. And they made a really strategic decision, which is to let people who are using codecs to code more efficiently use open source, open weight model tokens in addition to just OpenAI token.
30:25
And that is a STARK departure from the historical, you know, cursor sells to Elon and the models shut off access to their models to cursor. That's where we were quite recently. And now in a few weeks, we're in a place where at least OpenAI has said we want to win at the horizontal application layer, which means we have to go multi model architecturally. So I really like that move. I think it's genius, actually, and I think they're still going to sell a lot of OpenAI tokens into codex in the same way that ostensibly and actually Microsoft was open architecture with its OS.
31:12
You could use WordPerfect. You could use Lotus one, two, three. You could use freelance graphics. But over time, the market share shifted to Microsoft Word, Excel and PowerPoint because they own the playground, they own the operating system. And that was just a massive advantage, even if they weren't overtly bundling them in a way that triggered the regulators and in a way that actually forced lock We'll see what Anthropic does, but these are the kind of chess moves that are happening right now that I think make this such a fascinating place to watch.
31:44
I mean, there's a rumor going around the valley right now that both companies are going to shut off API access to vertical apps. That's a paranoid rumor that I don't think makes any sense because the API businesses are their biggest businesses. So how would that work? What's incentive? Well, the incentive would be you can only get the frontier models from applications they build. And so if you're Goldman Sachs and you're buying an AI application layer tool and you can go to a you know, you can go to Hebia, but you know, they can't get anthropic tokens or you can use anthropic for finance and get, you know, those sweet, sweet anthropic tokens.
32:31
That would be the logic. Again, I'm I'm skeptical. I think that's it. It would be a bad business decision. And OpenAI has just shown they're actually going in the other direction, much more open architecture versus closed. But these are the kind of theoreticals that are getting mooted right now.