Why the Best Trading Signals Still Begin With Primary Sources like 10-Ks and Earnings Calls

AlphaPro Editorial7 min read

There is an old saying in English, In today's investing, the broth is investment decisions. As information keeps pouring in from left, right, and center, making any sort of investing decision with a fair level of confidence has become more difficult than ever.

Every day we see inputs arriving like volcanic eruptions: rapid-fire news updates, opinions on X, influencer threads, and analyst notes and ratings. While each of these elements promises greater clarity as to which stocks to buy, together they make investing decisions overwhelming.

The good news, however, is that beneath this stormy surface, there is a far more reliable and stable layer. This layer consists of primary documents — such as 10-Ks, 10-Qs, annual reports, and earnings call transcripts — which every public company is required to publish.

These filings form the legal, audited, unambiguous foundation upon which everything else in financial markets is built. Think of them as the truth layer. Everything else downstream — analyst commentary on CNBC, media reports, and stock-market chatter on social media — is essentially an interpretation of those key filings.

And here's another important part: AI can make these primary documents much more powerful. Smart AI tools can scan them faster, compare them better, highlight changes more efficiently, and surface insights that humans would need weeks to find.

But remember that these signals still come from the primary sources. This is why serious investors, even in the most automated era in market history, still begin their research where the truth resides: in the 10-K, the 10-Q, and the unscripted honesty of a live earnings call.

Why Primary Documents Are More Important Today than Ever

A company's official filings are still the most reliable thing you can read. Because they're not written to go viral, and they're definitely not designed to entertain. They exist primarily because companies are legally required to tell the truth — or, at least, the closest version of the truth they are willing to put on paper under regulatory oversight.

That reason alone makes these documents more trustworthy than the headlines or the hot takes that spin around on social media. It may not be fun reading a 10-K, but it won't lie to you the way market noise often does.

In a fascinating study, researchers looking at 251 SGX-listed companies discovered something interesting: there is a positive relationship between the readability of annual reports and a company's investments in the following year. The clearer a company's annual report is this year, the more it tends to invest in the following year.

That said, a WU Vienna study found that the readability of annual reports is extremely low, meaning most readers — including investors — do not finish them. The researchers conducted a survey on more than 23,000 users of digital annual reports over several months. They found that a lion's share of the readership comes from employees, students, customers, and job applicants, while private and institutional investors and analysts account for less than one-third (32.5%) of all readers.

The MD&A: The Part of the Filing Where Companies Quietly Tell You the Truth

Once you open a 10-K or an annual report, there's one section that should always get your full attention: the Management Discussion & Analysis (MD&A). This is where management cannot hide behind tables or numbers and actually explain what happened in the business: why margins moved, what demand looked like, what's working, what's not, and what's starting to worry them.

It's the one part of the filing where you get a sneak peek into how leadership actually thinks. If a company suddenly starts talking about nobody needs a PhD or a Wall Street badge to know something is off. But if you never read the MD&A, you will be the last to know — probably long after the stock has moved.

Footnotes: A Hidden Treasure Most Investors Never Open

Most people stop reading after glancing at the income statement, skimming the balance sheet, and maybe checking cash flow if they are feeling studious. But the real treasure (and sometimes, the real land mines) lie in the footnotes.

Footnotes are the place for all sorts of things that a company needs to reveal, but doesn't want to shout from the rooftops. The not-so-glorious stuff — pending lawsuits, debt covenants, lease obligations, and accounting changes that will quietly hit earnings next quarter — finds its way into the footnotes.

A footnote is powerful because it's legally required, audited, and placed there under strict rules. So it's not an opinion; it's an obligation. Studies show that when investors are deciding whether to invest, the balance sheet, cash-flow statement, and notes to the financial statements consistently rank among the biggest factors. In investing, the boring stuff matters more than the exciting stuff — sadly, many investors skip it.

Earnings Calls: The Only Place You Can Hear Management Think in Real Time

Earnings calls are a different kind of signal. More than simply words on a page, earnings calls combine emotion, tone, confidence, and hesitation. They are live, and nothing replaces actually hearing the voice of the people who are running the show. Earnings calls give you something extremely important: a glimpse into how management thinks.

A slight pause before answering a question on margins, a defensive tone when asked about competition, or a sudden change in how they talk about demand (). These tiny cues tell you exactly where management feels pressure.

Yes, most investors don't have time to listen to full calls. But listening to even 10-15 minutes puts you in the top few percent of investors. And when you pair audio with AI-powered analysis, you get both the story and the subtext. This is where tools like AlphaPro Sentiment Score come into play.

AI + Primary Sources: The Combo That Takes Your Investing to the Next Level

While the primary sources can give you real insights about which stocks to pick, the hard thing about them is that they take time. A 10-K can run 200 pages, and a 10-Q isn't far behind. Footnotes can feel like they are designed to test your patience. Earnings calls are 45 minutes of management talking in circles, trying to say everything without saying anything.

This is exactly where AI is making life easier for serious investors. AI is built for the heavy lifting humans hate doing. It can tear through filings at lightning speed, compare this year's wording to last year's, highlight every shift in tone, and surface the exact sections you should care about. This means instead of spending three hours hunting for one new risk disclosure, AI hands it to you instantly.

AI summaries strip out filler, zoom in on what changed, and help you focus on what actually matters. The real magic happens when you combine the raw truth of primary sources with the analytical horsepower of AI. That's when real insight appears — the kind most investors never see.

And this is where AlphaPro fits perfectly.

One of the most powerful features we have built is the AlphaPro Earnings Sentiment Score. It's a tool designed to read an earnings call the way a highly trained human would, only faster and without bias. It runs every line of the call through advanced LLMs, tracks the tone of management, maps emotional signals, identifies hesitation, confidence, deflection, and stress, and then distills all of that into a single, simple score.

When the Earnings Sentiment Score turns sharply positive or negative, the stock often follows. Because tone reflects reality before the real numbers show up. AlphaPro quantifies verbal cues and gives you a potent tool to select better stocks. The key point is that AI transforms primary sources from time-consuming documents into fast, actionable signals.

Conclusion: The Real Edge Still Comes from the Source — AI Just Unlocks It

If there's one idea to walk away with, it's this: in a world full of noise, shortcuts, and surface-level summaries, your best signals are still hiding in the primary documents every company is required to publish. The 10-K, the 10-Q, the MD&A, the footnotes, the earnings call — these are the sources where the truth lies and where real investing begins.

And tools like AlphaPro take that one step further, reading earnings calls the way a seasoned investor would. It picks up tone, energy, confidence, and discomfort and then reduces all of that into a single score you can act on.

The world is only going to get noisier because the fire hose of opinions is only going to grow. But the companies you invest in will keep filing their documents, quarter after quarter, year after year. If you ground yourself in those primary sources — and let AI help you read them smarter and faster — you end up with something rare today: clarity in a market built on chaos.