High-conviction insider buying by sector in 2026 shows a clear concentration: biotech, semiconductors, and industrials have attracted the most unusual insider purchases this year, with cluster buying as the dominant pattern. Through the first five months of 2026, we've evaluated over 19,000 equity purchases filed with the SEC. Of those, 142 reached Elite tier and 697 reached Strong tier. Together, these 839 high-conviction trades represent roughly $748 million in insider capital deployed.

These are the top insider signals that historically beat the market, and where they concentrate tells you where the people running companies see value that the market doesn't. Data runs through May 29, 2026; sector groupings are editorial rather than based on standardized industry codes.

Biotech and pharma: cluster buying at scale

The strongest sector-level signal in early 2026 has been in biotech and pharmaceutical companies. Multiple companies have seen coordinated buying across their leadership teams, the kind of cluster activity that historically correlates with insider conviction about near-term catalysts.

The most striking example: Shattuck Labs (STTK), where the Chief Medical Officer, Chief Business Officer, and Chief Technical Officer all purchased stock on the same day in January, totaling over $5.6 million in combined personal capital. All three trades reached Elite tier. When three C-suite executives independently decide to buy at the same time, it suggests shared conviction about something not yet reflected in the stock price.

Alumis Inc. (ALMS) saw a similar pattern, with a director and multiple 10% owners making purchases within a 48-hour window in January, each deploying around $5 million, all reaching Elite tier. Day One Biopharmaceuticals (DAWN) saw its CEO invest nearly $4 million.

Biotech has always been a sector where insiders have outsized information asymmetry. Clinical trial data, regulatory timelines, and partnership discussions are material events that executives know about well before the market. Historically, insider buying in biotech and healthcare has produced stronger short-term returns than most other sectors: the independent r/ValueInvesting backtest of 906,000 Form 4 filings published in April 2026 found a +4.8% average return at 5 days for healthcare insider purchases, compared to roughly flat returns in sectors like real estate.

For European investors unfamiliar with US biotech insider filings, the concentration here is worth noting. The EU's Market Abuse Regulation imposes strict closed periods around material events, which limits when European executives can trade. In the US, the rules are different: insiders can trade right up until they possess material non-public information, and the two-day filing requirement means investors see those trades almost immediately.

Semiconductors: the February wave

Semiconductor insiders came in heavy during February 2026, with a cluster of large purchases from senior executives at several major chip companies.

Texas Instruments CFO Rafael Lizardi made two separate open-market purchases: roughly $8.4 million in February and $6.9 million in April. Both reached Elite tier. A CFO buying twice in three months, at this scale, is notable. CFOs have the most granular view of a company's financial trajectory. Repeat buying from the same CFO suggests sustained conviction, not a one-off.

Microchip Technology CEO Steve Sanghi purchased over $10 million in February, also reaching Elite tier. Advanced Energy Industries saw both its CEO and CFO buy on the same day in late February, a classic cluster pattern. Knowles Corp CEO Jeffrey Niew bought nearly $6 million the day before.

The February timing is relevant. Semiconductor stocks had pulled back through late 2025 and early 2026 on concerns about cyclical inventory correction and AI capex sustainability. The executives running these companies were buying into that weakness. Entegris' Executive Chair bought $3.6 million in early February. By late April, GE Vernova's CEO was still buying: $3.3 million, reaching Elite tier.

This pattern of insiders buying during a sector pullback rather than at highs is consistent with what the broader research shows about the contrarian nature of insider purchases. The Wall Street Journal's February 2026 analysis of S&P 500 insider buying found that 69% of insider buys happened after a price decline in the prior 30 days. In semiconductors, February 2026 was that window.

Industrials: C-suite conviction in heavy equipment

The industrial sector saw concentrated buying from the highest-ranking executives at some of the largest companies in the space.

Caterpillar had two Group Presidents buy within the same week in early February: Denise Johnson deploying roughly $10 million and Bob De Lange adding approximately $7 million across two purchases. Both reached Strong or Elite tier. A dual purchase from two Group Presidents at a $170 billion industrial company is unusual by any measure.

Deere & Co CEO John May bought over $10.6 million in early January. United Rentals CEO Matthew Flannery purchased $11 million at the end of January. Generac CEO Aaron Jagdfeld added $3.6 million in February. All reached Elite or Strong tier.

These are CEOs and senior leaders at cyclical industrial companies buying during a period when the market was debating whether the post-pandemic capex cycle had peaked. If it had, these executives apparently disagreed, at least enough to commit eight figures of personal capital.

Energy and mining: the persistent buyer

Energy and natural resources saw a different pattern: fewer companies, but unusually persistent buying from the same insiders.

The most notable: Eric Sprott, a 10% owner in Hycroft Mining (HYMC), made four separate purchases across a two-week window in January, each reaching Elite or Strong tier. When the same insider buys repeatedly in a compressed timeframe, it signals more than casual portfolio allocation. It suggests a thesis they're actively building a position around.

Kodiak Gas Services CEO Robert McKee bought over $10 million in March (Elite tier). International Seaways saw a 10% owner deploy nearly $12 million the same week. Kosmos Energy had a director invest $6 million.

Energy insider buying tends to concentrate in windows where commodity prices or sector sentiment create what insiders perceive as mispricing. Unlike tech or biotech, where information asymmetry comes from product pipelines, energy insider buying often reflects conviction about macro fundamentals: production costs, reserve values, and commodity cycles that executives understand better than external analysts.

The outlier: Rush Street Interactive

One company stands out for the sheer coordination of its insider buying. Rush Street Interactive (RSI), an online gaming company, saw its CEO, CFO, and COO all purchase on the same day in early January. All three reached Elite or Strong tier. A full C-suite buying simultaneously is rare in any sector; it happened at fewer than a dozen companies in our 2026 dataset.

What the patterns tell us

Cluster buying, contrarian timing, and high-asymmetry sectors defined the strongest insider signals of 2026 so far.

Cluster buying dominated the strongest signals. The most compelling trades in 2026 haven't been isolated purchases. They've been coordinated buys from multiple insiders at the same company: Shattuck Labs, Advanced Energy Industries, Caterpillar, and Rush Street Interactive all saw multiple executives buying within days of each other. This pattern consistently produces stronger subsequent performance than single-insider purchases.

February was the peak window. More high-conviction insider purchases occurred in February 2026 than any other month. This coincided with earnings season and a broader market pullback in several sectors. Insiders were buying into weakness, the contrarian pattern that academic research identifies as the most informative type of insider activity.

Biotech and semiconductors showed the strongest sector-level concentration. These are both sectors characterized by high information asymmetry: insiders know things about product pipelines, design wins, and technology roadmaps that external investors can't easily assess. It's consistent with the broader finding that insider buying carries the most informational content in sectors where the gap between insider knowledge and public knowledge is widest.

The specific trades cited here reflect SEC filing data and model tier classifications, not a view on any individual security.

Related Reading

• Not All Insiders Are Equal: Which Roles Produce the Strongest Signals: Why the C-suite buyers behind these sector waves carry the strongest signals.
• What Happens When You Invest $100 in Every High-Conviction Insider Signal for a Decade: How Elite and Strong signals like these performed over a ten-year simulation.
• The Timing Edge: Why Speed Matters in Insider Trading Signals: Why catching these sector waves early matters more than catching them at all.

For informational purposes only. Not investment advice.