Daily Insider Signal · July 21, 2026
Insider Alert: Tien Bor-Zen Bought TSM Shares (90/100 Signal)
Ticker
TSM
Action
Bought
Shares
1,000
Signal Score
90/100
Tien Bor-Zen bought 1,000 shares of TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD (TSM) at $73.98 for a total transaction value of $73,980.
This trade scores 90/100, indicating very high conviction. Large open-market purchases by C-suite executives with minimal noise factors are rare and historically correlated with positive 90-day forward returns.
The purchase increased the insider's holdings by approximately 50%, a significant position expansion that often signals strong internal confidence.
What to watch: Monitor upcoming earnings dates, any subsequent Form 4 amendments, and cluster activity (multiple insiders buying within a 30-day window). Single-insider signals are most powerful when corroborated by broader insider clustering or supportive technical trends.
This trade scores 90/100, indicating very high conviction. Large open-market purchases by C-suite executives with minimal noise factors are rare and historically correlated with positive 90-day forward returns.
The purchase increased the insider's holdings by approximately 50%, a significant position expansion that often signals strong internal confidence.
What to watch: Monitor upcoming earnings dates, any subsequent Form 4 amendments, and cluster activity (multiple insiders buying within a 30-day window). Single-insider signals are most powerful when corroborated by broader insider clustering or supportive technical trends.
What this signal means
DisclosureSignals scores every SEC Form 4 filing on a 0–100 scale. This trade earned a 90/100 signal score by weighing the transaction type, insider role, trade size, cluster buying, the insider's own history, and whether the trade was discretionary rather than part of a scheduled 10b5-1 plan. A higher score indicates a more unusual, conviction-driven purchase. Read the full methodology.
See every recent Form 4 filing for TSM, including historical insider trades and trend context.
Transaction Details
- Insider
- Tien Bor-Zen
- Company
- TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD
- Transaction Date
- July 21, 2026
- Price Per Share
- $73.98
- Total Value
- $73,980
- Type
- Purchase
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