Reporting owner · CIK 0001473289

Seifert Thomas J

SEC Form 4 history across 1 companies, 28 transactions and 3 filings.

CFOChief Financial OfficerCloudflare, Inc.
Open-market transaction mix0% buys0 buys · 19 sales
Latest filingSep 21, 2026, 08:50 PM

Available history · Aug 15, 2026 – Sep 17, 2026

Filings3Form 4 records
Buying$00 purchases
Selling$6.4M19 sales
Net value−$6.4MBuys minus sells · disclosed values

Latest insider transactions

Form 4 filings from available history.
Seifert Thomas J transactions · 20 per page
CompanyInsiderActivityDisclosed valueFiled (ET)
NETCloudflare, Inc.
Seifert Thomas JCFOS · sale10b5-1 detectedSEC filing ↗-$62.4kView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOS · sale10b5-1 detectedSEC filing ↗-$92.7kView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOS · sale10b5-1 detectedSEC filing ↗-$955kView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOS · sale10b5-1 detectedSEC filing ↗-$754kView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOS · sale10b5-1 detectedSEC filing ↗-$901kView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOS · sale10b5-1 detectedSEC filing ↗-$274kView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOC · unknown10b5-1 detectedSEC filing ↗UnknownView disclosure →
NETCloudflare, Inc.
Seifert Thomas JCFOF · withholdingSEC filing ↗-$929kView disclosure →
Open a transaction for shares, transaction date, ownership and the original SEC filing.

Latest Form 4 facts

Quick context from source filings

Latest open-market transaction

sale at Cloudflare, Inc. on Sep 17, 2026 valued at $33,651.

Review SEC filing
Latest buy

No open-market insider purchase is available.

Monthly open-market activity

Last 2 reported months · purchases and sales

View exact monthly values
MonthPurchasesSalesBuy valueSale valueNet value
Aug 202607$0.00$3,073,175.89-$3,073,175.89
Sep 2026012$0.00$3,324,617.43-$3,324,617.43

Net value is disclosed purchases minus sales, not profit. A dash means the value is unavailable.

Ownership and transaction size

Ownership and ticket size

Average P/S size$336.7K
Median P/S size$230.6K
Direct28
Indirect0
Sep 17, 2026unknown

Filing-only signals

Deterministic matches in this insider's history

Cluster Sellingpattern12Derivative Transactionfiling-context6Direct Ownershipfiling-context28Large Holdings Increaseholdings2Large Holdings Reductionholdings3Large Salesize2Repeat Sellerpattern1510b5-1 Detectedfiling-context27

Associated companies

Companies in the disclosed reporting history

Cloudflare, Inc.NET · 78 transactions · latest Sep 21, 2026, 08:50 PMWOLFSPEED, INC.WOLF · 1 transactions · latest Feb 03, 2025, 09:16 PM

Open-market buy performance

90-day forward return on this insider's open-market purchases

90d forward
No open-market purchases in available history

A 90-day purchase return requires an open-market buy. No eligible purchases are recorded in this history.

Disclosed ownership

How reported shareholdings evolved

Non-derivative shares held after reported transactions—not stock prices or a complete portfolio.

22 observations · Aug 15, 2026 – Sep 17, 2026. Window ends at the latest available report, not today.

Selected observation · Sep 17, 2026107,902 shares reported
Inspect transaction
View exact observations and source transactions
Transaction dateShares held afterFiledSource
Aug 15, 2026110,846Aug 18, 2026View transaction
Aug 17, 2026120,846Aug 19, 2026View transaction
Aug 17, 2026119,946Aug 19, 2026View transaction
Aug 17, 2026117,002Aug 19, 2026View transaction
Aug 17, 2026114,546Aug 19, 2026View transaction
Aug 17, 2026111,446Aug 19, 2026View transaction
Aug 17, 2026111,146Aug 19, 2026View transaction
Aug 17, 2026110,946Aug 19, 2026View transaction
Aug 17, 2026110,846Aug 19, 2026View transaction
Sep 17, 2026117,902Sep 21, 2026View transaction
Sep 17, 2026117,802Sep 21, 2026View transaction
Sep 17, 2026117,702Sep 21, 2026View transaction
Sep 17, 2026117,602Sep 21, 2026View transaction
Sep 17, 2026117,302Sep 21, 2026View transaction
Sep 17, 2026116,602Sep 21, 2026View transaction
Sep 17, 2026115,902Sep 21, 2026View transaction
Sep 17, 2026114,706Sep 21, 2026View transaction
Sep 17, 2026113,102Sep 21, 2026View transaction
Sep 17, 2026110,470Sep 21, 2026View transaction
Sep 17, 2026108,602Sep 21, 2026View transaction
Sep 17, 2026108,002Sep 21, 2026View transaction
Sep 17, 2026107,902Sep 21, 2026View transaction

Securities and direct/indirect ownership contexts are kept separate and never summed. Joint filings may associate the same disclosed row with multiple owners. Unknown values are omitted, not treated as zero. Lines connect observations for readability; they do not establish holdings between filings, cost basis, or current ownership. Amendments and stock splits require reviewing the source.

Seifert Thomas J Insider Activity FAQ

SEC Form 4 context

Who is Seifert Thomas J?

Seifert Thomas J is a reporting owner in SEC Form 4 filings with reporting owner CIK 0001473289.

Which companies has Seifert Thomas J reported transactions for?

Cloudflare, Inc., WOLFSPEED, INC.

When was Seifert Thomas J's latest insider buy?

No open-market insider purchase is available for this period.

When was Seifert Thomas J's latest insider sale?

sale at Cloudflare, Inc. on Sep 17, 2026 valued at $33,651.

Where can I see the original SEC filings?

Each transaction row links directly to the source SEC filing so the reported Form 4 details can be reviewed.

Are performance metrics included?

The profile shows average and median 90-day stock returns after open-market purchases when price coverage is available. These are unadjusted stock returns, not realized trading gains. Win rates, benchmark-adjusted returns and conviction scores are not calculated.