Top Whale Tickers in Late September 2026: CrowdStrike, Snowflake, and Dell Lead Form 4 Flow

Top whale tickers in late September 2026 still skew heavily toward sales, but the names at the top of the board are shifting again. As of September 27, 2026, ProBors shows CRWD (CrowdStrike) with about $232 million in net reported whale value over 14 days—ahead of DELL on dollars even though DELL still leads on print count at 294 rows. SNOW (Snowflake) re-entered the top tier with 61 whale-class prints and roughly $140 million in net reported value, while STX (Seagate) remains a storage-sector headline on both frequency and dollars. This guide maps the late-September leaderboard, a five-step triage framework, recent large Form 4 filings worth a second look, and what leaderboard volume does not prove. It is research context, not investment advice.

Why the late-September whale board looks different from mid-September

Whale leaderboards rank large Form 4 prints by frequency and reported value—they are not sentiment scores. Three changes stand out compared to the board as of September 20:

• CrowdStrike moved up on dollar volume. CRWD shows 148 whale-class prints and about −$232 million in net reported value in 14 days, with officer code S sales filed September 25, 2026, after September 24 trade dates. Mid-September commentary focused on DELL and CHYM; CRWD now competes for the top slot on net value even though print count is lower than DELL.
• Dell’s print count cooled as the rolling window advanced. DELL still leads frequency at 294 prints (down from 615 in the prior mid-month window) with about −$210 million in net reported value. Silver Lake-affiliated fund distributions remain the story—hundreds of code S lines—not a single officer headline.
• Snowflake joined the high-dollar tier. SNOW ranks in the top 15 by both prints (61) and net reported value (about −$140 million), driven in part by a $17.0 million officer sale filed September 24, 2026.

The overall pattern—zero open-market buys on most top names, heavy code S flow on liquid tech—persists. The research task is which tickers deserve a footnote read this week, not whether the board is “bearish.”

14-day whale leaderboard (as of September 27, 2026)

The table below reflects ProBors whale activity over the last 14 days as of September 27, 2026. Print counts include large Form 4 rows indexed in the platform; net reported value sums directionally (sales show as negative).

Over 30 days, DELL still dominates print count (888 rows, zero buys, about −$784.1 million in net reported value), followed by CRWD (259 prints, about −$257.6 million) and STX (181 prints, about −$245.0 million). The 30-day view confirms sustained fund-holder distribution on DELL and recurring officer selling on cybersecurity and storage names—not a one-week anomaly tied to a single headline.

Note on mixed codes: Tickers like EBAY and OKTA can show large net values with low code S counts in the buy/sell split because disposition (D), conversion, and other Form 4 codes also flow through whale feeds. Open the underlying filing before treating a rank as a directional signal.

A five-step triage framework for loud whale tickers

Use the same checklist when a ticker tops the late-September board so tax withholding rows and fund distributions do not masquerade as discretionary flow.

1. Confirm the SEC transaction code

Open-market sales use code S; open-market purchases use code P. Grants (A), dispositions (D), conversions (C), and option exercises (M, X) are different economic events. ProBors shows the code and trade type on each whale row—filter here before reacting to dollar size.

2. Separate fund-holder waves from officer sales

DELL illustrates why this matters: Silver Lake-affiliated entities file dozens of code S lines on the same trade dates, often split across multiple tranches. A $30 million officer sale on CRWD or a $17 million officer sale on SNOW reads differently than a PE-holder distribution program spanning hundreds of rows.

3. Measure filing lag in calendar days

Form 4 is generally due within two business days after the transaction. A one-day lag on a September 24 trade filed September 25 is routine. A four-day gap on a large sale—like some DELL officer rows filed September 21 after September 17 trade dates—deserves a footnote read on SEC EDGAR.

4. Read signal scores as a sort key—not a verdict

ProBors signal scores weigh size, role, timing, and pattern history. A score of 5 on a multi-million-dollar officer sale flags attention but does not prove bearish intent—it may reflect size relative to that insider’s median print. A lower score on a fund distribution row can still be economically meaningful. Sort by signal after filtering codes. For scoring details, see how ProBors trade signal scores work.

5. Cross-check chart and congressional context

Open the ticker workspace on ProBors: review price reaction since the trade date, any congressional markers, and whether the AI summary flags earnings or lock-up events. Whale flow plus politician activity on the same name is a stronger research prompt than either feed alone.

Recent filings worth a second look

The table below shows deduplicated whale rows from ProBors as of September 27, 2026, filed in the last week of September. Values are as reported in the platform; lag is calendar days between trade date and filing date.

How to read this snapshot without overfitting:

• CRWD Podbere Burt W. filed multiple code S lines on September 24, 2026, filed September 25; the row above is one tranche in a larger same-day wave. High signal scores reflect size and clustering, not a fresh catalyst by themselves.
• SNOW Dageville Benoit’s $17.0 million sale filed September 24 pairs with other officer activity on the name in the same week—read the full Form 4 for exercise and plan footnotes.
• DELL Kennedy David Alan’s $13.5 million sale shows a 4-day filing lag relative to the September 17 trade date—unusual enough to verify timing on EDGAR, separate from Silver Lake fund distributions.
• NTRA Sheena Jonathan filed many code S lines across September 23–25; the table shows one representative print rather than every tranche.

How to research whale tickers on ProBors

1. Open the Whales tab from the dashboard and sort by filing date (newest first).
2. Click Top tickers and toggle between 14-day and 30-day windows to see whether flow is sustained or rolling forward with the calendar.
3. Filter by ticker when CRWD, SNOW, or DELL hits your watchlist.
4. Open a row to read transaction code, insider title, signal score, and footnote context.
5. Jump to the Market workspace for the same ticker to overlay price action and congressional markers.
6. Add tickers with recurring whale prints to a watchlist if you want alerts on the next filing—not on live price.

For tab navigation details, see the ProBors Whales tab guide. For the full triage checklist, see how to triage whale transactions on ProBors.

What this whale data does not prove

A sell-heavy whale leaderboard does not prove:

• That insiders traded on material non-public information
• That a ticker will fall because officers sold shares or funds distributed holdings
• Exact share counts or post-trade holdings (Form 4 value fields are as reported, not always full position snapshots)
• That every code S row is discretionary—many reflect 10b5-1 plans, tax events, or PE rebalancing
• That zero buys on a leaderboard ticker means no insider interest (smaller purchases below whale thresholds may exist elsewhere in Form 4 data)
• That CRWD or SNOW officer sales this week predict near-term price direction

Insider selling and fund distribution is often routine. The research value is prioritization: which tickers deserve a footnote read, a chart check, and a second pass against the original SEC filing.

FAQ

What counts as a "whale" transaction on ProBors?

ProBors surfaces large Form 4 filings that meet size thresholds for the Whales feed—typically high-dollar open-market prints and other reportable rows that stand out from routine compensation activity. Use transaction code and reported value together, not size alone.

Why does CRWD rank above DELL on net value but below on print count?

CRWD carries fewer whale-class rows (148 vs 294 on DELL) but larger per-line officer sales in the current 14-day window—about −$232 million net reported value vs about −$210 million on DELL. DELL’s count is inflated by many smaller fund-holder code S lines from Silver Lake-affiliated entities.

Why did Snowflake reappear on the late-September board?

SNOW shows 61 prints and about −$140 million in net reported value as the rolling 14-day window picked up large officer sales filed September 24, 2026, including Dageville Benoit’s $17.0 million code S row. It was less prominent on the mid-September top-ten list when CHYM and ATAI dominated dollar headlines.

How is late September different from mid-September on the whale board?

Mid-September leaderboards emphasized DELL at 615 prints and post-IPO CHYM fund sales. Late September shows a lower DELL print count in the rolling window (294), CRWD leading on net reported value, and SNOW in the high-dollar tier. STX and UTHR remain active; SE and TVTX stay in the top ten by frequency.

Should I short a stock because it tops the whale leaderboard?

No. Leaderboard volume is a research queue, not a trading signal. Verify each row on EDGAR, read footnotes for 10b5-1 plans, and treat the data as disclosure context. This is research context, not investment advice.

How often does ProBors refresh whale data?

Form 4 ingestion runs on a regular schedule. Check probors.com/status for the latest SEC Form 4 / Whales source health before citing rows in notes or publications.

Track whale flow on ProBors

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Related reading

• Top whale tickers in mid-September 2026
• Dell whale insider sales explained
• How to triage whale transactions on ProBors
• Datadog whale insider sales explained
• Why insider selling is usually not a signal

Sources

• SEC Form 4 overview — reporting requirements for insiders
• SEC EDGAR search — verify individual Form 4 filings
• SEC investor bulletin: Forms 3, 4, and 5
• Rows were checked in ProBors and should be verified against the original filing.
• Ingestion health: probors.com/status