Who Is Judah Spinner?
Judah Spinner is an American investor, philanthropist, and the founder and Chief Investment Officer of BlackBird Financial LP, a value-oriented investment partnership based in Toms River, New Jersey. BlackBird manages nearly $90 million on behalf of high-net-worth individuals and family offices across North America, applying a concentrated, long term approach grounded in the principles of Benjamin Graham and Warren Buffett. Spinner, who is only thirty, is also a Chartered Financial Analyst and proud member of the CFA Institute, having passed all three levels of the CFA exam on his first attempt, a feat accomplished by fewer than one in ten candidates.
In 2025, when the S&P 500 returned 17.9%, Judah Spinner returned 62.2% to his partners. He did it the way he’s done everything since he bought his first stock at thirteen, by ignoring almost everything the market was paying attention to and focusing on the handful of businesses he’d spent years studying. His portfolio rarely holds more than a few names at a time, and he has been known to commit as much as half the fund to a single position. He calls it the punchcard philosophy, after Buffett’s thought experiment that investors would perform far better if limited to just twenty investments over a lifetime. I sat down with him to talk about Builders FirstSource, how a thesis actually comes together, the path from Lakewood to Wall Street, and the three causes he and his wife are backing through the Judah Spinner Foundation.
In March 2026, BlackBird Financial increased its stake in Builders FirstSource by 900% — a dramatic move made as the stock was falling. What were you seeing that the rest of the market wasn’t?
I’d been watching Builders FirstSource for a long time, hoping the market would hand me an opportunity to build a real position, and the ever-compliant Mr. Market eventually obliged. The stock sold off hard on weakness in the U.S. housing market, and we bought between $80 and $100 a share. With roughly 110 million shares outstanding, that put the market cap around $10 billion. I think the business is worth substantially more than that. Wall Street was fixated on short-term noise — the war in Iran, oil prices, what earnings were going to look like next quarter. The only question I care about is what this company looks like in ten years.
And when you look out ten years, the picture is very different from what the quarterly crowd sees. The industry has consolidated dramatically. A decade ago the four largest players in building materials distribution were Builders FirstSource, ProBuild, BMC, and Stock Building Supply, four competitors grinding each other down in what was a brutally commoditized industry. Today all four are one company. The product mix is also shifting toward higher-margin value-added products like trusses, wall panels, and engineered wood. On top of that, management has retired close to half the outstanding shares in just a few years. And the macro backdrop is powerful: every year since 2008 we’ve built fewer homes than the number of new households being formed, and America is now millions of homes short. Just as the surplus after 2008 suppressed building for a decade, that shortage will eventually force a sustained building boom. Put it all together and it was a no-brainer at these prices.
Once you’ve identified a company like Builders FirstSource, how does a thesis like that actually come together? How long had you been watching before you acted?
Years, in most cases. The real work happens long before the trade. I try to turn every page, to build a mental catalog of hundreds of businesses, understanding how they make money, how a management team operates, what margins look like in good times and bad, and what a reasonable price is. You’re training your mind to recognize quality and to recognize value, so that when an opportunity shows up you can actually see it for what it is. You want your mind fully prepared and stocked with information, because that’s what makes your judgment high-quality when it finally matters. Most of what you read never turns into an investment. That’s fine. The reading isn’t wasted, it’s what makes you capable of acting when the moment arrives.
And you never know when that moment will come. A company you’ve followed for five years is well run and you understand it well, but it sells at too expensive a price. Then one day the market panics about something short-term, and suddenly a business you know inside and out is on sale. That’s the fat pitch. If you haven’t done the work in advance, you can’t swing, by the time you’ve figured the company out, the price has moved. I’m just trying to feed my mind lots of information, and upon occasion, I’ll stumble onto something intelligent to do.
You grew up in Lakewood and made your first investment at thirteen. How did you end up running a fund by eighteen?
Markets caught my attention unusually early. I was reading The Wall Street Journal every morning by the time I was twelve, and at thirteen I bought my first stock — seventy-four shares of Target at $40.50 each. A couple of years later, I was introduced to Charles Dayan, a prominent New York real estate investor, through his son, who was a friend of mine. He decided to hand me $100,000 to manage. I was fifteen. It was an extraordinary gesture, and I’ve always been grateful for it — he was betting on a teenager, and that’s not something most people are willing to do.
From there it moved quickly. I worked as a securities analyst at Spencer Winston Securities and Track Data Corporation in Brooklyn, and on October 1, 2014, a few weeks before I turned nineteen, I founded Petlin Management — the firm that eventually became BlackBird Financial. I feel enormously fortunate to have found what I love this early in life. Most people spend decades looking for work that fits them. I’ve been doing the same thing, in essentially the same way, since before I was old enough to vote, and I plan on doing it until they carry me out.
You invested in Dollar General in late 2024 and sold it about fourteen months later for more than a 100% profit. Walk me through the thesis.
We made the initial investment on November 22, 2024, at a $16 billion market cap. Dollar General operates more than 20,000 locations and generates $40 billion in annual revenue, and a few things about the business stood out. Nearly 80% of their stores are in towns with fewer than 20,000 residents — places where there just isn’t room for much competition. Even Walmart, one of the most well run retailers in the country, tried to challenge them in those markets and ultimately retreated in the mid-2010s. The unit economics are exceptional: opening a new store takes about $300,000 in capital, and the average location generates $160,000 in annual operating profit. That’s the kind of return on invested capital that compounds beautifully over time.
On top of that, management had been disciplined about how they deployed cash, No big, value destructive acquisitions like their primary competitor had done, just organic expansion and returning capital to shareholders through buybacks and dividends. And at a $16 billion market cap, the normalized earnings yield was comfortably in the double digits. Put all of that together, a durable competitive position, terrific unit economics, sensible management, and a cheap price, and it was an easy decision. Fourteen months later the market had come around to the same view, the stock had more than doubled, and we sold at a level where the margin of safety we’d bought into no longer existed.
Beyond the investment work, you and your wife also run the Judah Spinner Foundation, which focuses on a pretty specific set of causes — a trade scholarship, healthcare reform, and federal deficit reduction. What drew you to those particular issues?
Because I believe they are the most pressing issues facing the country. The scholarship is the most personal of the three for me. Income inequality in the United States is the widest it’s been in forty-five years, and the bottom quartile of households by income simply have not shared in the prosperity the rest of the country has enjoyed since 1980. Helping people become well-paid tradesmen is one of the most direct ways I can think of to actually do something about that. The country is short hundreds of thousands of electricians, welders, HVAC technicians, and plumbers — jobs that pay well, require a fraction of the time and money of a college degree, and are in demand everywhere. I also appreciate that the return per dollar we invest in this initiative is fantastic: for a relatively small cost per student, we can dramatically increase their lifetime earnings.
Healthcare is the second cause, and it’s closely tied to the third. The United States spends more on healthcare than any country in the world, by far, roughly 18% of GDP, and gets worse outcomes than countries spending a fraction of that. Singapore spends about 5% and has a life expectancy five years longer than ours. The good news is that, so long as we can get Congress to cooperate, we don’t need to reinvent the wheel, we can replicate systems that we already know work well. The solutions exist. What’s missing is the political will to adopt them.
The federal deficit is the third cause. The federal government now owes more than $39 trillion, and what’s most concerning is that the debt continues to grow at an unsustainable pace even during peace and economic expansion. What happens if we need to ramp up spending in the next recession?
What makes this issue particularly dangerous is that as the debt builds, the pain is deferred, which breeds a level of complacency in Congress. Both Republicans and Democrats have acknowledged the problem, but neither party has shown any real urgency in finding a solution. By the time the Treasury has difficulty selling its bonds and major disruption ensues, it will be too late. I hope it never gets to that point, but if we don’t get our act together, that eventuality is inevitable.
The good news is that progress on healthcare costs would go a long way toward resolving the deficit problem as well. A large share of federal spending goes to Medicare and Medicaid, so the single most powerful lever for reducing the deficit is bringing healthcare costs down. If we got U.S. healthcare spending to Singapore’s levels, the government would save close to a trillion dollars a year — enough to push the federal deficit below 3% of GDP, which is a genuinely sustainable level.
All three of these issues will take enormous effort, significant resources, and a fair amount of luck to resolve. I don’t know how successful we’ll be, but we’re going to give it a try.
Throughout our hourslong conversation, Spinner returns often to a maxim from Warren Buffett: “price is what you pay; value is what you get”. It is the mindset he applies to everything he does. At BlackBird, it means waiting patiently for the rare moment when a great business can be purchased at a bargain price. The same discipline carries into his philanthropic efforts, where, for example, the incremental lifetime earnings of a tradesman dwarfs the modest outlay for their training. In the final analysis, Spinner’s pursuit is consistent: buying a dollar for 50 cents.
