Ankur

Regular tax firms don't grow like this. They stop taking clients after December and only grow 10% YoY. @fifteenth_tax is doing something different. We've been growing 20% MoM for the last 6 months, and it's only accelerating into this tax season. Why are we able to accept so much inbound? Because our CPAs are 10x more effective. All the grunt work is done by AI agents while humans provide expertise at the tail end, ensuring better client experience and higher accuracy! PS we are still taking on clients (yes, even in March!)

@fifteenth_tax is the tax solution for innovators!

It's a good day when you get a dozen sign ups before the morning coffee ☕️

@lihararora I'd say 30B+. Given their market position, they are quite likely to hit 3-4B rev in the next few years.

@ankurd What do you think is the fair valuation? I know the market valued it at $80B only a few months ago but that seemed too crazy for the company's fundamentals and $1B ARR.

Wild that Figma is trading at a $17B valuation. One of the few true monopolies in tech right now!

Gemini 3 is a phenomenal model. Most of our evals went up by ~5% and are now >= human scores. Thanks @GoogleAI!

@immad @davidu We’re doing the tax part of this @fifteenth_tax

@davidu Would take meeting. I need this. I do feel like there are some people already building this but no winners yet.

Respond to this tweet with a startup idea. I will tell you whether I would take a investor meeting or not and why for that idea, assuming it came in from a strong warm intro. I can tell in 280 chars whether an idea is interesting to me and why. Maybe it will be useful feedback.

🚨 Leaderboard Update Claude Opus 4.1 Thinking by @AnthropicAI debuts in the Text & WebDev Arenas - going straight to the top. 🚀 A few highlights: 💠Claude Opus 4.1 is now the only model to rank #1 across all major categories 💠#1 Overall, tied with three other models: gpt-5-high, Gemini-2.5-pro, and Claude Opus 4.1 💠#1 in WebDev & Coding, showing strong real-world coding performance Learn more about what the community prompts and votes reveal about Claude Opus 4.1 Thinking in thread 👇

On our evals, GPT5 does slightly worse than Claude 4 Sonnet and takes 4x longer! To be fair, the prompt isn't tuned for GPT5 but still a bit disappointing - definitely doesn't feel like a SOTA model.

Caveats: SALT = state + property taxes. These reduce taxable income up to the cap. But: – Cap starts phasing out above $500K income – Fully back to $10K by $600K+ income So this mainly helps folks in the $300K–500K range.

Big win for CA/NY residents in the BBB: the SALT cap jumps from $10K to $40K. If you’re earning in the mid six figures and paying big in property/state taxes, that’s an extra $5K–$10K in your pocket.

I’m not big on identities, but I am extremely proud to be American. This is true every day, but especially today—I firmly believe this is the greatest country ever on Earth. The American miracle stands alone in world history. I believe in techno-capitalism. We should encourage people to make tons of money and then also find ways to widely distribute wealth and share the compounding magic of capitalism. One doesn’t work without the other; you cannot raise the floor and not also raise the ceiling for very long. The world should get richer every year through science and technology, but everyone has to be in the “up elevator”. I think the government usually does a worse job than markets, and so we need to encourage our culture of innovation and entrepreneurship. I also believe that education is critically important to keeping the American edge. I believed this when I was 20, when I was 30, and now I am 40 and still believe it. The Democratic party seemed reasonably aligned with it when I was 20, losing the plot when I was 30, and completely to have moved somewhere else at this point. So now I am politically homeless. But that’s fine; I care much, much more about being American than any political party. I’d rather hear from candidates about how they are going to make everyone have the stuff billionaires have instead of how they are going to eliminate billionaires. The American experiment has always been messy. I am hopeful for another great 250 years. Happy 4th!

Our Resource Center is built for folks navigating equity events, IPOs, and comp complexity. Getting this right could save you thousands in taxes! Start learning: fifteenth.com/resource-center

If you work (or worked) at Scale, Figma, Gusto, or Rippling — you need to check this out We just launched @fifteenth_tax's new Resource Center with: ✅ Webinars on tender offers & stock options ✅ Deep dives on QSBS & RSU taxation ✅ Practical insights for tech professionals

@dnlkwk @Austen 100% agreed. We are doing 0->1 at fifteenth.com - started with zero clients and already serving hundreds across top tech startups!

@Austen def not trivializing that part in any way. will be immensely difficult. my only point is that that will be easier (and more fun) for founders than driving internal transformation in a 300 person accounting firm in Missouri

As someone who did this for 3 years + helped raise $600M fund for it, I am incredibly bearish. At face value, the thesis of AI + existing company = multiple and profit margin expansion sounds genius to every VC investor. However, ask any veteran PE investor about operational improvements and internal transformations, and they'll tell you that those founders will burn themselves out trying to transform the company from within. There's a better way to do these types of deals.

The agents are starting to work real well 👀

Calling c the "speed of light" completely misses the point. Rather, c is the "spacetime exchange rate": how many units of space you can exchange for one unit of time. In actuality, everything travels at the "speed of light", just not necessarily through space alone... (1/4)

What if April 15th were just another day? @Ankurd and @LauraMoreno_CPA, founders of @fifteenth_tax, are transforming tax preparation for complex financial situations. Their platform identifies missed deductions, optimization opportunities, and planning considerations by analyzing your return. Building what's essentially an AI-enhanced CPA firm for those of us (no comment) with complex tax situations. Better taxes. No dread. We backed them last year alongside @GeneralCatalyst, @A_StarVC (thanks to @GGuptaSF for the intro), and @SVAngel. We're proud of the work they've done applying AI to revolutionize an industry ready for change.

Forward logo still up on an abandoned building in SF. Feels like a warning sign to every healthtech founder walking by.

Claude 4’s agentic capabilities are really impressive - we saw our eval scores jump from 93% to 96% while cutting latency by 20%!