The Trade Desk (“TTD“) is the worst-performing company in the S&P500 this year, down 62%. If we go back one more year, the decline is 90%.Ouch.So naturally, I got curious to understand what is going on here, and it’s really, really bad.Subscribe now1.0 IntroductionA lot of advertising goes to Google, Meta, Amazon, or TikTok. But can you trust that they’re making the best choice for you? Are they choosing the right slot for you, or the right slot for them?All of these companies own ad space, so it is not an unreasonable question.That’s where The Trade Desk comes in. It owns no ad inventory.Every time a page or app loads, an auction runs for the ad slot in a fraction of a second before you see anything. Millions of these happen every second, and TTD looks at each one and decides, in milliseconds, whether it is worth bidding on and how much. Its revenue is ~20% of the gross spend.Almost all of the platform's spend comes from large Fortune 500 companies.So, whether it’s a streaming app, podcast, recipe blogs, or anything else that’s online with ad space, the flow is similar, and it all goes down to the highest bidder.But they are not alone.2.0 How’s TTD different than the competitors?There are two arguments:Objectivity: The company doesn’t own the ad inventory, so choosing the right ad slot is not biased. Google keeps a lot more of the transaction if the ad goes to YouTube instead of Netflix.Data neutrality: Nike’s campaign data won’t be used to help Adidas. One can argue that this is a disadvantage. Wouldn’t you want the best RoI for the customers? Yes, but here’s the other side of the coin. Not all advertisers contribute equally. Imagine if Nike spent a lot of money, and TTD figured out how to reach the best audience (from an RoI point of view). Then, Adidas comes to the platform and is just a free-rider on the knowledge that Nike paid for. In this example, Nike would be considered a “net donor“, and would not be happy. But the net donors are exactly the customers that TTD attracts.In the past, they had another advantage in the Connected TVs (“CTV“).The company covered all premium connected TV plus the open web. This was huge. If anyone wanted Disney, Hulu, Paramount, or Roku inventory programmatically, TTD was the way to go. Many advertisers came because TTD had access to inventory nobody else had.But now Google’s DV360 and Amazon DSP exist as alternatives.DV360 also plugs into the Google stack (Campaign Manager, Analytics, YouTube) in one workflow.Amazon has purchase data at scale, as it knows what people have actually bought. On top of that, there’s the Prime Video inventory.Both of these competitors can afford to run the bidding at 0% margin, as they earn on the ad space (and on the products sold).I am not convinced that objectivity and data neutrality are strong enough to keep advertisers paying a premium when likely cheaper alternatives exist. I am using the word "likely" because the fees from Google/Amazon are not disclosed.Let’s have a look at the numbers.3.0 Historical financial performance (and lack of operational leverage)You might ask, well, if they have no competitive advantage, why does the chart below look the way it does?For roughly 5 years, TTD was the only route to ads on Disney, Hulu, Paramount, or Roku, at scale.The revenue growth since 2018 was:55% —> 39% —> 27% —> 43% —> 32% —> 23% —> 26% —> 18% —> and now, in Q2-2026, only 3%.Next quarter? Decline to $650m, representing:9% decline vs. Q2-202612% decline vs. Q3-2025What is going on? The management “blames” the CPG and auto segments, as both of those are under tariff and oil-price pressure and represent ~25% of the business. This shows how concentrated the customer base is, and that TTD is a cyclical business.But more importantly, TTD is no longer the only player when it comes to Connected TVs. This is huge. Competing with Google/Amazon is no joke. I expect them to apply more pricing pressure on TTD over time, leading to lower revenue (or fewer customers), which will translate into lower margins.The company is proud to have 95%+ customer retention. This is insufficient. If the customers start spending less, sure, quantity-wise, they’ve stayed. But they are less valuable.Lastly, there was exclusivity with Walmart, which is no longer the case. I think more similar contract changes will follow, harming TTD.The management’s tone in the last quarter was defensive. Pointing fingers helps nobody. In my view, it’s clear that this is a difficult industry to operate in, and it will only get more competitive.But before I go to some more bad news, I was surprised to see no operating leverage. The margin is roughly the same. If I look at the contribution per employee, it’s not impressive at all (pretty much inflation-related).4.0 CFO turnover (and audit)Normally, C-level executives don’t change roles often.TTD had 4 different CFOs in 1 year.Not many public companies can say that.There were other senior members who were replaced. Why? One can only speculate.Next to that, in March 2026, Publicis published a 3rd party study, alleging that TTD had charged fees beyond contractual limits and enrolled clients into paid features without consent. This dispute was resolved in June 2026 without any details on the settlement terms, or whether any financial adjustments were made. The only information was that Publicis would resume recommending the platform. That’s it.Four CFOs in a short period of time, while a large customer is accusing the company of overcharging, is quite unusual.5.0 Capital allocationPersonally, I dislike the business. But the capital allocation? It’s worse.The company is generating free cash flow. In H1-2026, it generated $427m (of which $218m was related to share-based compensation, which is a real cost).The cash generated was used to buy back shares (started in 2023).2023: $647m (estimated average share price $64)2024: $235m (estimated average share price $94)2025: $1.4b (estimated average share price $53)H1-2026: $241m (estimated average share price $23)As I am writing this, the share price is $14, and the market cap is $6.6b.In these 3.5 years, the company spent $2.5b and reduced the shares outstanding by only 4%.Thank you for reading the deep dive; I hope you find it valuable. Consider subscribing so you get the next ones in your inbox.6.0 ValuationPersonally, I see too many red flags and weaknesses.I am not saying there’s no chance to turn it around, but I wouldn’t bet on it. I don’t feel comfortable having it in my portfolio as I don’t see any moat.My best estimate is that the Google/Amazon pressure will continue, and it’ll take a few years for the revenue to stabilize, but it will stabilize at lower margins (15% operating margin vs. 20% today).Based on the above assumption, TTD is worth ~$5.1b ($11/share) vs. today’s market cap of $6.6b (14/share).At today’s price, the market is implying that the operating margin will be ~18% and the company will go back to growing its revenue at ~3%/year. Is this possible? Absolutely. I just don’t feel comfortable betting on that.If you own this company and you’re convinced that the growth will be above what is implied, I wish you nothing but success.The Finance Corner is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber.This is NOT investment advice. Everything above is for entertainment, informational, and educational purposes. Do your own due diligence.