SEC Form 4
Rambus Inc (RMBS) insider trading
In the 12 months to Oct 26, 2026, 10 RMBS insiders reported open-market sales of $21.0M across 19 filings; no open-market purchases were filed.
Latest filing · Last 12 months · Source: SEC EDGAR · How we count
- Open-market sales
- $21.0M
- 19 filings · 10 insiders
- Open-market purchases
- $0
- 0 filings
- Pre-arranged sales (10b5-1)
- 10 of 19
- $8.7M of $21.0M sold (41%)
Who traded RMBS, and when
- Sale
- Sale, pre-arranged (10b5-1)
RMBS daily close from Oct 27, 2025 to Oct 26, 2026, between $79.73 and $170.66, last $91.83. 19 sale and 0 purchase filings by 10 insiders, marked at their filing dates. Xianzhi Sean Fan, EVP, COO: sold $5.8M across 1 filing, first filed May 26, 2026, last May 26, 2026. Luc Seraphin, President and CEO: sold $4.4M across 2 filings, first filed Mar 3, 2026, last Apr 3, 2026. Emiko Higashi, Director: sold $2.4M across 2 filings, first filed May 27, 2026, last Jun 3, 2026. Necip Sayiner, Director: sold $2.1M across 2 filings, first filed May 11, 2026, last Jun 3, 2026. Eric B. Stang, Director: sold $1.7M across 2 filings, first filed Nov 12, 2025, last Jun 2, 2026. Charles Kissner, Director: sold $1.6M across 3 filings, first filed Aug 10, 2026, last Oct 5, 2026. 4 others: sold $3.1M across 7 filings, first filed Feb 24, 2026, last May 26, 2026.
Largest mark · tap a row for others
Xianzhi Sean Fan · EVP, COO
Sale $5,751,226
37,914 shares at $151.69 avg
Filed May 26, 2026
Close on filing date $157.23
Xianzhi Sean Fan · EVP, COO
EVP, COO
$5.8M soldLuc Seraphin · President and CEO
President and CEO
$4.4M soldEmiko Higashi · Director
Director
$2.4M soldNecip Sayiner · Director
Director
$2.1M soldEric B. Stang · Director
Director
$1.7M soldCharles Kissner · Director
Director
$1.6M sold4 others
Combined, one mark per week
$3.1M soldOpen-market trades
19 filings in the last 12 months| Insider | Role | Sold | Bought | Filings | Pre-arranged (10b5-1) | Last filed |
|---|---|---|---|---|---|---|
| Xianzhi Sean Fan | EVP, COO | $5.8M | — | 1 | — | |
| Luc Seraphin | President and CEO | $4.4M | — | 2 | 100% of sales | |
| Emiko Higashi | Director | $2.4M | — | 2 | — | |
| Necip Sayiner | Director | $2.1M | — | 2 | — | |
| Eric B. Stang | Director | $1.7M | — | 2 | — | |
| Charles Kissner | Director | $1.6M | — | 3 | 100% of sales | |
| Meera Rao | Director | $1.5M | — | 2 | 100% of sales | |
| John Shinn | SVP, General Counsel | $974.0K | — | 3 | 85% of sales | |
| Desmond Lynch | SVP, CFO | $433.8K | — | 1 | 100% of sales | |
| Steven Laub | Director | $188.3K | — | 1 | — |
| Filed | Insider | Type | Shares | Avg price | Value | Held after | Source |
|---|---|---|---|---|---|---|---|
traded | Charles Kissner Director | SalePre-arranged (10b5-1) | 5,000 | $111.00 | $555.0K | 3,747 | |
traded | Charles Kissner Director | SalePre-arranged (10b5-1) | 5,000 | $105.00 | $525.0K | 8,747 | |
traded | Charles Kissner Director | SalePre-arranged (10b5-1) | 5,000 | $100.92 | $504.6K | 13,747 | |
traded | Emiko Higashi Director | Sale | 10,000 | $160.50 | $1.6M | 54,519 | |
traded | Necip Sayiner Director | Sale | 5,000 | $170.15 | $850.8K | 18,223 | |
traded | Eric B. Stang Director | Sale | 5,000 | $146.00 | $730.0K | 19,218 | |
traded | Emiko Higashi Director | Sale | 5,000 | $157.57 | $787.9K | 59,519 | |
traded | John Shinn SVP, General Counsel | Sale | 1,000 | $143.63 | $143.6K | 21,112 | |
traded | Xianzhi Sean Fan EVP, COO | Sale | 37,914 | $151.69 | $5.8M | 168,458 | |
traded | Steven Laub Director | Sale | 1,500 | $125.52 | $188.3K | 7,519 | |
traded | Necip Sayiner Director | Sale | 9,824 | $130.18 | $1.3M | 23,223 | |
traded | Meera Rao Director | SalePre-arranged (10b5-1) | 2,972 | $150.30 | $446.7K | 19,974 | |
traded | Meera Rao Director | SalePre-arranged (10b5-1) | 8,538 | $118.08 | $1.0M | 22,946 | |
traded | Luc Seraphin President and CEO | SalePre-arranged (10b5-1) | 5,426 | $86.65 | $470.2K | 345,932 | |
traded | John Shinn SVP, General Counsel | SalePre-arranged (10b5-1) | 4,556 | $88.68 | $404.0K | 18,467 | |
traded | John Shinn SVP, General Counsel | SalePre-arranged (10b5-1) | 4,557 | $93.55 | $426.3K | 25,326 | |
traded | Luc Seraphin President and CEO | SalePre-arranged (10b5-1) | 39,914 | $98.63 | $3.9M | 369,305 | |
traded | Desmond Lynch SVP, CFO | SalePre-arranged (10b5-1) | 4,273 | $101.53 | $433.8K | 63,618 | |
traded | Eric B. Stang Director | Sale | 9,000 | $106.54 | $958.9K | 20,394 |
GET /stocks/filings/vX/form-4?tickers=RMBS&filing_date.gte=2025-10-26&sort=filing_date.desc&limit=500{
"status": "OK",
"results": [
{
"tickers": [
"RMBS"
],
"issuer_cik": "0000917273",
"owner_cik": "0001188095",
"accession_number": "0001193125-26-413981",
"form_type": "4",
"filing_date": "2026-10-05",
"period_of_report": "2026-10-02",
"issuer_name": "RAMBUS INC",
"issuer_trading_symbol": "RMBS",
"owner_name": "KISSNER CHARLES",
"is_director": true,
"is_officer": false,
"is_ten_percent_owner": false,
"is_other": false,
"security_type": "non_derivative",
"record_type": "transaction",
"security_title": "Common Stock",
"transaction_timeliness": "O",
"aff_10b5_one": true,
"transaction_date": "2026-10-02",
"transaction_code": "S",
"equity_swap_involved": false,
"transaction_shares": 5000,
"transaction_price_per_share": 111,
"transaction_acquired_disposed": "D",
"shares_owned_following_transaction": 3747,
"transaction_value": 555000,
"direct_or_indirect": "I",
"nature_of_ownership": "See Footnote",
"footnotes": [
{
"id": "F1",
"description": "The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted on May 8, 2026."
},
{
"id": "F2",
"description": "All shares sold at an exact price of $111.00."
},
{
"id": "F3",
"description": "The shares are held directly by Kissner and Associates LLC for which the Reporting Person serves as the owner of the company."
}
]
},
{
"tickers": [
"RMBS"
],
"issuer_cik": "0000917273",
"owner_cik": "0001188095",
"accession_number": "0001193125-26-400762",
"form_type": "4",
"filing_date": "2026-09-24",
"period_of_report": "2026-09-22",
"issuer_name": "RAMBUS INC",
"issuer_trading_symbol": "RMBS",
"owner_name": "KISSNER CHARLES",
"is_director": true,
"is_officer": false,
"is_ten_percent_owner": false,
"is_other": false,
"security_type": "non_derivative",
"record_type": "transaction",
"security_title": "Common Stock",
"transaction_timeliness": "O",
"aff_10b5_one": true,
"transaction_date": "2026-09-22",
"transaction_code": "S",
"equity_swap_involved": false,
"transaction_shares": 5000,
"transaction_price_per_share": 105,
"transaction_acquired_disposed": "D",
"shares_owned_following_transaction": 8747,
"transaction_value": 525000,
"direct_or_indirect": "I",
"nature_of_ownership": "See Footnote",
"footnotes": [
{
"id": "F1",
"description": "The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted on May 8, 2026."
},
{
"id": "F2",
"description": "All shares sold at an exact price of $105.00."
},
{
"id": "F3",
"description": "The shares are held directly by Kissner and Associates LLC for which the Reporting Person serves as the owner of the company."
}
]
}
]
}
// trimmed to 2 resultsThe response includes every Form 4 record; this page keeps open-market purchases and sales on common stock and removes duplicate joint-filer rows.
Other insider activity (not market trades) · 30 records
- Tax withholding10 records
- Grants and awards18 records
- Gifts2 records
Reported on Form 4 but not purchases or sales in the market, so not counted in the totals above.
How to read this page
- Open-market purchase or sale
- A buy or sell of the company's stock at market price. Grants, option exercises, shares withheld for tax, gifts and employee stock plan purchases are listed separately and not counted.
- Pre-arranged (10b5-1)
- The insider marked the filing as made under a trading plan set up in advance (SEC Rule 10b5-1). The mark covers the whole filing, and an unmarked filing may still be under a plan.
- Filing date
- Insiders have two business days to report a trade. Totals and the chart use the filing date, when the trade became public.
Frequently asked questions
Has Rambus Inc's CEO sold stock?
Yes. Luc Seraphin (CEO) sold 45,340 shares ($4.4M) between Mar 2026 and Apr 2026, all under a pre-arranged 10b5-1 plan.
How current is RMBS’s insider data?
These are RMBS Form 4 filings from the last year, refreshed daily. The Massive Form 4 API has the full, continuously updated record.
What counts as an open-market buy or sell?
Only purchases and sales at the market price. Option exercises, grants, gifts, and shares withheld for taxes are reported on Form 4 but are left out of the buy and sell totals.
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