Matheos Mark sold ~$2.4M in Appian Corporation stock
Appian Corporation (APPN) · Chief Financial Officer · Data via SEC EDGAR Form 4
Price Performance · 10 days before → 90 days after trade
▲ = insider buy date
90-day return
-26.8%vs SPY +3.4%
Trade Details · Public SEC Filing
Insider
Matheos Mark
Role
Chief Financial Officer
Transaction
Open-Market Sale
Approx. Value
~$2.4M
Trade Date
Sep 11, 2023
Company
Appian Corporation
Ticker
APPNSource
SEC EDGAR Form 4
Why This Trade Stands Out
Strong conviction signal
Scored above average across multiple factors. Roughly 15% of insider trades qualify as Strong.
~$2.4M sale
Trades over $1M are rare. When insiders put this much of their own money on the line, they tend to have high conviction in their company's direction.
Chief Financial Officer
CFOs have direct access to financials before they become public. Their trades are among the most closely watched by institutional investors.
3 insiders traded in the same window
When multiple insiders independently buy within 30 days, it's called a cluster. Studies show clustered insider purchases outperform solo trades significantly, because several people with inside knowledge are reaching the same conclusion.
-26.8% in 90 days (S&P 500: +3.4%)
This trade underperformed the S&P 500 by 30.2 percentage points. Not every insider trade wins. We track all of them so you can focus on the insiders with the best records.
How good is Matheos Mark at picking stocks?
Full track record: win rate, average return, and performance vs S&P 500
Matheos Mark wasn't the only one selling.
3 insiders at Appian Corporation traded within the same 30-day window.
See who else bought · FreeOn September 11, 2023, Matheos Mark — Chief Financial Officer of Appian Corporation — filed a Form 4 with the SEC disclosing an open-market sale of approximately ~$2.4M in Appian Corporation (APPN) stock.
This transaction was part of a cluster — 3 insiders at Appian Corporation made open-market sales within the same 30-day window. Cluster activity from multiple independent insiders is one of the most studied patterns in insider trading research.
Under Section 16(a) of the Securities Exchange Act of 1934, corporate insiders must report all open-market stock transactions to the SEC within two business days. These filings — known as Form 4s — are publicly available on the SEC's EDGAR database. VeritySignals filters and scores the full Form 4 stream to surface high-conviction signals like this one.
In the 90 days following this trade, APPN returned -26.8% versus +3.4% for the S&P 500 over the same period.
VeritySignals Conviction Analysis
Full Conviction Analysis
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All data sourced from publicly available SEC Form 4 filings via EDGAR · Not financial advice · Past performance does not guarantee future results.
At a Glance
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How to Read Insider Trades
What is this?
When company executives buy or sell their own stock, they must report it to the SEC within 2 days. These public filings reveal what the people who know the company best are doing with their own money.
Why does it matter?
Insiders can sell for many reasons (taxes, diversification, expenses), but they generally only buy for one: they think the stock is going up. That's why insider purchases are more predictive than sales.
What makes a trade "strong"?
We score trades on 15+ factors: the insider's role (CEO > director), trade size relative to their salary, whether other insiders also bought (clusters), and historical accuracy of the insider.
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