Insider ownership percentage answers "does management have skin in the game?" Insider buying answers a sharper question: "is management putting new, post-tax personal money in right now, and why?" These are two different signals built from two different kinds of data — a static shareholding percentage versus a rolling window of actual transactions — and they're useful in different situations. This post covers the second one: screening recent insider buying activity, not the ownership stake itself.
If you're looking for the ownership-percentage version of this screen — founder and family stakes, European ownership culture, the 15–40% "sweet spot" — see insider ownership screening. This post is about transactions: who bought, how much, and how recently.
Last updated: July 2026.
Ownership percentage vs. buying activity: two different signals
Insider ownership (%) is a snapshot: at this moment, what fraction of the company do insiders collectively hold? It's slow-moving and mostly reflects history — IPO allocations, option exercises over years, family inheritance. A founder holding 30% today may not have bought a single share in the open market in a decade.
Insider buying (transactions) is a flow: in a recent window (this screen uses a rolling 90-day view), which insiders bought shares, how many, and how does that compare to selling activity over the same period? This is a live signal about current conviction, not historical allocation.
A company can score low on the ownership screen (professional management, minimal historical stakes) and still throw off a strong buying signal (the new CFO just bought €200k of stock on the open market three weeks after joining). The two screens catch genuinely different situations, and the strongest combined signal is often rising ownership through recent purchases — a director who didn't previously own much stock and has just started buying meaningfully.
Why insider buying is a stronger signal than insider selling is a warning
The core asymmetry that makes insider buying useful: insiders sell for many reasons unrelated to their view of the company (diversification, tax planning, a house purchase, options about to expire), but they only buy for one reason — they believe the stock is worth more than the current price, and they're willing to risk personal, after-tax capital on that view.
This is why professional investors weight insider buying much more heavily than insider selling as a screening signal. A single insider sale is close to noise. A cluster of insider purchases — especially from multiple different insiders, or following a share price decline — is much harder to explain away.
Signals worth weighting most heavily:
- Multiple different insiders buying in the same window — reduces the chance it's one person's idiosyncratic personal financial planning
- Buying after a price decline — signals conviction that the drop is not justified by fundamentals
- CEO or CFO buying (versus a non-executive director) — the roles with the deepest visibility into the business
- Purchase size relative to the insider's existing stake or salary — a token purchase is a weaker signal than one that represents a meaningful personal commitment
How to screen for insider buying
Net buy value as the primary filter
The cleanest starting filter looks at net insider buying value over a trailing window (buys minus sells, in currency terms) — positive net buying across a company's insiders over the past 90 days is a materially different situation from net selling.
Basic insider buying screen:
- Insider net buy value (90d) > €0 (net buyers, not just gross buyers)
- Insider buy count (90d) ≥ 2 (more than one transaction — reduces noise from a single trade)
- Sort by: insider net buy value descending
Combined with a price decline
One of the more actionable patterns: insider buying that follows a meaningful drawdown, where the buying reads as a considered response to a lower price rather than routine compensation-related activity.
Contrarian insider buying screen:
- Insider net buy value (90d) > €0
- Price change (3-month) < -15% (recent decline)
- Net Debt/EBITDA < 3.0 (rules out buying that's really just insiders averaging down on a business heading into distress)
- Sort by: insider net buy value descending
Combined with fundamentals
Insider buying is a timing and conviction signal, not a substitute for fundamental quality. Combining it with a baseline quality filter avoids following insiders into structurally weak businesses.
Quality + insider conviction screen:
| Filter | Value |
|---|---|
| Insider net buy value (90d) | > €0 |
| Insider buy count (90d) | ≥ 2 |
| Operating margin | > 8% |
| Net Debt/EBITDA | < 3.0 |
| Market cap | €50M–€2B |
| Sort by | Insider net buy value descending |
The market cap band matters here: insider buying is a more informative signal in small- and mid-cap names, where a single insider's personal capital represents a meaningful position relative to daily trading volume and where fewer analysts are already pricing in the same information.
Why this matters more in small- and mid-cap Europe
Insider buying is diluted as a signal in heavily covered mega-caps, where a director's purchase is a rounding error relative to daily volume and where the stock is already priced by dozens of analysts pricing in every scrap of public information. It's a much sharper signal in the small- and mid-cap segment of European markets that ScreenerHero focuses on:
- Less analyst coverage means insiders have a genuine informational edge relative to the market, rather than simply confirming what's already priced in
- Lower trading volume means an insider purchase represents a larger relative commitment and is harder to dismiss as portfolio noise
- Family and founder-led companies (common across German, Italian, and Nordic small caps — see insider ownership screening) often have insiders who are also operators with the deepest visibility into near-term performance
Common mistakes when screening insider transactions
Treating any single sale as a red flag: Insiders sell for reasons unrelated to their view of the company far more often than they buy for reasons unrelated to conviction. A single sale, even a large one, is weak evidence on its own — check whether it's isolated or part of a broader pattern of net selling across multiple insiders.
Ignoring transaction size relative to the insider's position: A director buying €5,000 of stock is a much weaker signal than one buying €500,000, even though both show up as "insider buying" in a binary screen. Where the data is available, weight by transaction value, not just transaction count.
Chasing buying without any fundamental filter: Insiders are people, and people are sometimes wrong, overconfident, or buying for reasons that don't hold up (a personal belief the market will eventually recognise a thesis that turns out to be mistaken). Use insider buying as a supporting signal alongside a baseline quality and leverage screen, not as a standalone thesis.
Applying it uniformly across mega-caps and small caps: The signal is strongest where insider capital is a meaningful fraction of daily liquidity and where coverage is thin — exactly the segment where large US-centric screeners tend to have the weakest European data.
Bottom line
Insider ownership percentage and insider buying activity answer different questions. Ownership tells you whether management's long-run incentives are aligned with shareholders. Buying activity tells you whether insiders are putting new capital in right now, and that's a timelier, higher-conviction signal — particularly when it comes from multiple insiders, follows a price decline, or comes from the executives with the deepest visibility into the business. Screen for net buying activity over ownership percentage alone when the question is "what's happening right now," and combine both with a baseline fundamental filter before treating either as an actionable thesis.
Frequently asked questions
Is insider buying a reliable signal for European small caps?
It's one of the more useful supporting signals, particularly for small- and mid-cap European names with thin analyst coverage, where insiders have a genuine informational edge. It's strongest when multiple insiders are buying, when the purchases follow a price decline, and when combined with a baseline fundamental quality filter rather than used in isolation.
What's the difference between insider ownership and insider buying?
Insider ownership is a static percentage — how much equity insiders collectively hold right now, largely reflecting history (IPO allocations, option exercises, inheritance). Insider buying is a flow — recent open-market purchase transactions, which reflect current conviction and require new, post-tax personal capital. A company can have low insider ownership and still show a strong recent insider buying signal, or vice versa.
Should I ignore insider selling entirely?
Not entirely, but weight it much less heavily than buying. Insiders sell for many reasons unconnected to their view of the company — diversification, tax planning, expiring options, personal liquidity needs. A single sale, even a sizeable one, is weak evidence. Persistent net selling across multiple insiders over an extended period is a more meaningful signal than any single transaction.
Is insider transaction data available for European stocks?
Coverage varies by market. Major European exchanges require insider transaction disclosure above certain thresholds, but the consistency and timeliness of that reporting differs by jurisdiction — it is generally more standardised for large caps than for micro-caps. Where available, ScreenerHero surfaces recent net insider buying activity alongside fundamental filters in the screener.
Screen European stocks by insider buying activity → — free, no account required. Filter by recent insider transactions, fundamentals, and leverage across all European exchanges.