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Arena reached a $100M annual revenue run rate just 8 months after launching our evaluation product. We started as a research project at UC Berkeley with a simple mission: measure AI progress through real-world use. As AI shifts from chatbots to agents taking on longer, higher-stakes work, the problem matters more than ever. Today, Arena measures real-world AI utility with a community of tens of millions. With Agent Arena, we’re evaluating long-running agents on complex, real-world tasks - how they use tools, adapt to feedback, recover from errors, and accomplish goals set by humans. We are excited to keep deepening our work in agentic evaluations. Here’s @ml_angelopoulos on what this milestone means and where we go from here:

Today, I’m excited to formally announce @mirendil with my amazing co-founders Harsh Mehta, Shayan Salehian, and Tara Rezaei! We’re fortunate to work with @a16z and @kleinerperkins, who led our seed round of $200M, followed by a major investment from NVIDIA, among others. Mirendil exists to accelerate science and technology, and through them, to help solve humanity's most pressing problems. Self-accelerating AI R&D is the most direct path to delivering on AI's broader promise, which is why we believe the most important application of AI is AI itself. Get this loop right, and it compounds. It fundamentally changes the rate of progress itself across all domains. We believe this capability should be democratized. It should be used to power all scientific efforts trying to innovate at the frontier. There are far more important problems—and broader ones—than any single lab can take on, so more groups should be able to pursue them. This pulls concentration of power away from a few labs: businesses and science labs can own their AI and infrastructure, keep their margins, and control their own destiny instead of ceding it all to a single AI lab. We’re a small team with a singular focus. Our founding team consists of 20 researchers and engineers from frontier institutions including Anthropic, xAI, Google DeepMind, and OpenAI, united by a passion for science and a drive to build the technologies that move it faster. If you want to build the system that builds systems, join us! @HarshMeh1a, @shayan_, @tararezaeikh

Folks, I am closing the books on—gasp—15 years at Andreessen Horowitz. I am still in awe of what we’ve built and do not take for granted these past 15 years, which have felt like 15 minutes in some respects. When the inimitable @wennmachers invited me onboard (I think I was employee number 20-something and thought we were already a sizable firm!), it was to build the brand of a16z and to raise the profile of one @bhorowitz. (Fun fact: One of my first announcements was how the firm had raised a combined $2.7B in our first three years, and one of my last was the $15B we’d closed in January, with now over $100B under management across multiple funds.) While Ben has been a key throughline in my journey, along the way I also had the tremendous privilege and responsibility of leading marketing—first, for our enterprise investing team and portfolio, and later, for our growth fund and portfolio. Both of my boys, now 11 and 7, also came into the world during this time, so a16z is interwoven into the fabric of our lives. I remain beyond proud of the work that we, the marketing team, did over the years, so much of it unsung and behind the scenes. Maybe this time around, I should write the book and Ben, as he once jokingly told me, would do the marketing for it. To know that the brand of a16z is now part of my legacy is remarkable. What makes a place is the people and I take with me some of my deepest friendships. You know who you are and I cannot imagine these past many years without you. ❤️ And to Margit, who made this journey possible, so much love and respect for you. 🙏 As for what’s ahead, I’m fully embracing what I believe to be the true ethos of the firm, which is to expect the unexpected. After a tenure like mine, I really have to close this door before I can even think about opening another, so the only plan I have is to take a well-earned break this summer with my family. 🙌 In the words of my own TeamG, more TK!

En Palacio Nacional, recibimos a Ben Horowitz, cofundador y socio general de la firma financiera Andreessen Horowitz. Coincidimos en que México es ejemplo de confianza y certeza económica.

Almost 12 years ago, I left @DRWTrading with @wesarn_real to start @digitalasset. @ShaulKfir joined us shortly after. The name felt right. The idea was simple but audacious: build a global settlement system that is asset agnostic. One that doesn’t eliminate banks, exchanges, and intermediaries, but tears down the barriers keeping people from accessing assets and settling at a fraction of today’s cost. A new financial world, built for the end consumer. We knew institutional adoption was the path. We just didn’t know how long it would take. We failed. We made bad decisions. There are things we would have done differently. But we never let go of our North Star, even when people around us were convinced we had no idea what we were doing. That focus, conviction, and most of all, patience, led us to launching @CantonNetwork. And the results speak for themselves. Today is a new chapter in that story. I’m proud to announce that @a16zcrypto is leading our latest round, joined by some of the giants of the global financial system, including @ABNAMRO, ADIA, @apolloglobal, @BNPParibasCIB, @Broadridge, @citsecurities, @CMEVentures, @cbventures, Green Wolf Asset Management, @Hanwha_Official, @HSBC, @icapitalnetwork, @LCVentures, @OptiverGlobal, @polychain, @R136Ventures, @SPGlobal, @sbigroup, @smash_capital, @SoFi, @Tradeweb, and @WilliamBlair, and others we’ll be naming shortly. Twelve years ago, I could not have imagined building alongside partners of this caliber. $CC today processes the highest fees of any institutional blockchain network. And we’re just getting started. What’s coming later this year is just as exciting. None of this happens without the builders, the ones who show up to weekly tokenomics meetings, dial into operations subcommittees, spend nights and weekends building apps on Canton, and show up on @X to cheer this ecosystem forward. You are not just supporters. You are partners. I’m honored to be on this journey with you. On a personal note: @a16z hits differently for me. Ben’s book The Hard Thing About Hard Things was one I kept coming back to during the hard stretches. Having his firm lead this round is meaningful in a way that’s hard to put into words. So I’ll let him do it: “The hard thing isn’t setting a big, audacious goal. The hard thing is spending sleepless nights trying to achieve it. The hard thing isn’t dreaming big. The hard thing is waking up in the middle of the night in a cold sweat when the dream turns into a nightmare. Motivating yourself by watching YouTube shorts or Instagram reels isn’t the hard thing. The hard thing is working every day and being consistent even if you feel like shit. The hard thing isn’t boasting you could achieve anything. The hard thing is working like hell to achieve something. The hard thing isn’t believing in yourself. The hard thing is getting things done when nobody believes in you, even when you doubt yourself. The hard thing isn’t telling yourself that you must achieve the impossible. The hard thing is toiling hard every day for years despite knowing that success is too uncertain.” theblock.co/post/404386/a1…

🇺🇸🚀 SOME NEWS: I'll be leaving my role at the White House at the end of this month. After a break I’ll be working on helping tackle some of the large challenges facing America on AI (more on that later). It is hard to express how big a privilege it has been to serve the American people and how grateful I am to have had the opportunity to do so. First and foremost, it has been an honor to serve under President @realDonaldTrump . Without his leadership, we would not be leading in the AI race. Second, I owe a lot to the person I’ve worked mostly closely with over the last 18 months - @DavidSacks . His continuing advocacy for America winning on AI has been and continues to be crucial. Some key public accomplishments from last year I’m proud of 1. Architecting and publishing the American AI Action Plan - charting the course for America to win on AI and helping execute on that for the last year. 2. The AI acceleration partnerships to help American AI stack win globally. 3. The National AI Policy Framework for Artificial Intelligence executive order (forming the basis for working with the Hill this year) 4. Advocating for the American AI stack with our allies globally (the AI summits in France and India, state visits to the UK, the Middle East and more) So what’s next? The past 18 months have given me a front row seat to this critical moment on AI facing America and our allies. Whether it is energy, data centers or a clear path for Americans to experience the benefits of AI, there are many tough issues we all need to navigate together. I plan on building institutions that help tackle some of those challenges for America and its allies. I want to thank many others who have helped along the way in the administration : Kevin Hassett, @mkratsios47 , CoS @SusieWiles47 , VP @JDVance , @StevenCheung47 , Sec Bessent, Sec Lutnick, Sec Rubio and @jacobhelberg , @USWREMichael , Will Scharf, Taylor Budowich, @JamesBlairUSA , @elonmusk and many, many others. You know who you are and I know I’ll continue to see you a lot more. Most of all, I want to thank @aarthir on supporting everything and being part of this unexpected but amazing journey from last January. None of this would be possible without her. This journey has been the privilege of a lifetime and shown me how special this country is and how it needs all of us to contribute in anyway we can - and I plan on continuing to do just that. 🇺🇸

Today, I’m excited to join Andreessen Horowitz as a General Partner and Head of Global Affairs. This is my next chapter in the mission of securing America at home and ensuring technological innovations are adopted to keep us safe, working together with our allies to build a more secure and prosperous future. Today, as the U.S. and China compete on the global stage, the spread of technology is tinged with geopolitics and more fragmented. Security now requires a focus on digital sovereignty, supply chain resiliency, and the trustworthiness of the infrastructure underpinning our economies and our national security. My full announcement: a16z.news/p/technology-i…

Introducing Agent Arena: real-world agentic evals at scale. How do you evaluate agents doing actual work? We measure millions of live sessions where real users accomplish real tasks. On Arena, models now get web search, filesystem, and terminal tools to complete complex workflows: writing code, creating slide deck, researching the web, building apps, and analyzing documents. Every session produces rich signals. Users iterate with the agent turn-by-turn: approving, editing, correcting, praise or expressing frustration. The environment gives feedback too: shell errors, tool failures, recovery attempts, and more. Our leaderboard measures each model's agentic performance using causal inference across five signals: task success, steerability, error recovery, user praise vs. complaint, and tool hallucination. This leaderboard snapshot is built from 300K+ tasks, 2M+ tool calls, and 40M lines of code by agents. Top labs in Agent Arena: - #1 @OpenAI: GPT-5.5 (High) - #2 @AnthropicAI: Claude-Opus-4.7 (Thinking) - #3 @Zai_org: GLM-5.1 - #4 @GoogleDeepMind: Gemini-3.1-Pro - #5 @Kimi_Moonshot: Kimi-K2.6 More analysis in the thread, with the full technical blog below.



Today, we’re launching @TownAI: the AI assistant that learns you. We’re coming out of beta with a $55M Series A led by @ARampell at @a16z, with participation from @KirstenGreen at @forerunnervc and continued support from @firstround, @altcap, and @conviction. Right now, getting real value from AI means prompting, configuring, building workflows, managing agents. We think that’s backwards. The future of AI is a companion that already knows you and how you work. Town connects across your inbox, calendar, Slack, docs, messages, and workflows to understand what you need, then starts doing the work with you. Drafting. Scheduling. Project tracking. Follow-ups. Context gathering. Multi-step tasks. And it only acts when you say so. All adapting to your voice, priorities, routines, and relationships over time. Your Townie is the AI assistant you actually need.

本日、ベン・ホロウィッツ・共同創業者兼ゼネラルパートナーをはじめとする、アンドリーセン・ホロウィッツ(a16z)社の皆様にお越しいただき、今年夏に、米国内以外で初となる海外拠点を日本に設けることなどについて、御説明いただきました。 a16z社は、フェイスブック、インスタグラムなど多くのスタートアップを育成、支援した実績を有する世界最大級のベンチャー・キャピタルです。 高市内閣では、『日本成長戦略』の重要な柱として「新技術立国」を掲げ、スタートアップ・エコシステムの構築を目指しています。 また、「経済力」、「技術力」が、我が国の「外交力」、「防衛力」を決するという認識の下、17の戦略分野の一つとして防衛産業を位置づけています。 そうした中で、米国において、産業分野のイノベーションをリードし、安全保障に貢献するスタートアップを見出し、育成してきたa16z社が、「唯一の海外拠点」を日本に開設し、日本への投資拡大、起業家の育成に乗り出すことは、高市内閣の成長戦略、安全保障戦略を進めていく上で実に心強いことです。 日本のスタートアップ・エコシステムのダイナミズムを取り入れながら、経済の自律性、技術の優位性や不可欠性を確立することで、「安全保障と経済成長の好循環」を実現していきます。


本日、ベン・ホロウィッツ・共同創業者兼ゼネラルパートナーをはじめとする、アンドリーセン・ホロウィッツ(a16z)社の皆様にお越しいただき、今年夏に、米国内以外で初となる海外拠点を日本に設けることなどについて、御説明いただきました。 a16z社は、フェイスブック、インスタグラムなど多くのスタートアップを育成、支援した実績を有する世界最大級のベンチャー・キャピタルです。 高市内閣では、『日本成長戦略』の重要な柱として「新技術立国」を掲げ、スタートアップ・エコシステムの構築を目指しています。 また、「経済力」、「技術力」が、我が国の「外交力」、「防衛力」を決するという認識の下、17の戦略分野の一つとして防衛産業を位置づけています。 そうした中で、米国において、産業分野のイノベーションをリードし、安全保障に貢献するスタートアップを見出し、育成してきたa16z社が、「唯一の海外拠点」を日本に開設し、日本への投資拡大、起業家の育成に乗り出すことは、高市内閣の成長戦略、安全保障戦略を進めていく上で実に心強いことです。 日本のスタートアップ・エコシステムのダイナミズムを取り入れながら、経済の自律性、技術の優位性や不可欠性を確立することで、「安全保障と経済成長の好循環」を実現していきます。

Honored to see dripstack.xyz featured as the demo use case for agentic.market by @coinbase / @base !!! Now agents can access, reason over, and act on the best premium financial writing on the internet, while paying writers for the amazing content they create. Try it now: dripstack.xyz