Reporting owner · CIK 0001720721
Marmurek Eric S
SEC Form 4 history across 1 companies, 3 transactions and 1 filings.
EVP, CFOEVP, Chief Financial OfficerRibbon Communications Inc.
Open-market transaction mix—0 buys · 0 sales
Available history · Oct 15, 2026 – Oct 15, 2026
Latest insider transactions
Form 4 filings from available history.| Company | Insider | Activity | Disclosed value | Filed (ET) |
|---|---|---|---|---|
RBBNRibbon Communications Inc. | Marmurek Eric SEVP · CFO | M · exerciseDerivative securitySEC filing ↗ | $0View disclosure → | |
RBBNRibbon Communications Inc. | Marmurek Eric SEVP · CFO | F · withholdingSEC filing ↗ | -$21.5kView disclosure → | |
RBBNRibbon Communications Inc. | Marmurek Eric SEVP · CFO | M · exerciseSEC filing ↗ | UnknownView disclosure → |
Latest Form 4 facts
Quick context from source filings
Latest open-market transaction
No latest transaction fact is available.
Latest buy
No open-market insider purchase is available.
Latest sale
No open-market insider sale is available.
Monthly open-market activity
Last 1 reported months · purchases and sales
No open-market purchases or sales in this history.
View exact monthly values
| Month | Purchases | Sales | Buy value | Sale value | Net value |
|---|---|---|---|---|---|
| Oct 2026 | 0 | 0 | $0.00 | $0.00 | $0.00 |
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—
Median P/S size—
Direct3
Indirect0
Oct 15, 2026exercise
Filing-only signals
Deterministic matches in this insider's history
Associated companies
Companies in the disclosed reporting history
Open-market buy performance
90-day forward return on this insider's open-market purchases
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.
2 observations · Oct 15, 2026 – Oct 15, 2026. Window ends at the latest available report, not today.
Selected observation · Oct 15, 2026566,450 shares reported
Inspect transaction View exact observations and source transactions
| Transaction date | Shares held after | Filed | Source |
|---|---|---|---|
| Oct 15, 2026 | 581,206 | Oct 19, 2026 | View transaction |
| Oct 15, 2026 | 566,450 | Oct 19, 2026 | View 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.
Marmurek Eric S Insider Activity FAQ
SEC Form 4 context
Who is Marmurek Eric S?
Marmurek Eric S is a reporting owner in SEC Form 4 filings with reporting owner CIK 0001720721.
Which companies has Marmurek Eric S reported transactions for?
Ribbon Communications Inc.
When was Marmurek Eric S's latest insider buy?
No open-market insider purchase is available for this period.
When was Marmurek Eric S's latest insider sale?
No open-market insider sale is available for this period.
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.