Comparable stake leader
Frederik W. Mohn
SEC ownership of Transocean Ltd.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001451505.
Disclosed value leader
BlackRock, Inc.
Comparable rows
50/50
Latest evidence
31 Mar 2026
- Public ticker
- RIG on NYSE
- Parsed ownership sources
- 13D/G, 3/4/5, and 13F
- Largest SEC-reported holder
- Frederik W. Mohn
- Latest 13D/G holder
- Frederik W. Mohn
- Latest parsed ownership date
- 31 Mar 2026
- Issuer CIK
- 0001451505
- Issuer location
- Steinhausen, Switzerland
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Transocean Ltd. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Frederik W. Mohn
Disclosed value leader
BlackRock, Inc.
Comparable rows
50/50
Latest evidence
31 Mar 2026
13D/G
3/4/5
13F
Lead comparable stake: 8.8%
13D/G row: Frederik W. Mohn
Showing 1-8 of 50 holder rows.
Quick read
Frederik W. Mohn leads the comparable SEC ownership view at 8.8%.
50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Frederik W. Mohn's linked filing trail.
Comparable ownership
Top 5
Frederik W. Mohn
8.8%
BlackRock, Inc.
6.4%
Capital World Investors
4.6%
PRIMECAP MANAGEMENT CO/CA/
1.5%
DIMENSIONAL FUND ADVISORS LP
4.4%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Frederik W. Mohn |
13D/G
3/4/5
Director
|
8.8%
|
$400,272,583
96,918,301 shares
|
+$6,195,000 | 09 Feb 2026 |
| BlackRock, Inc. |
13F
13D/G
Company
|
6.4%
from 13D/G
|
$585,901,378
88,371,248 shares
|
— | 31 Mar 2026 |
| Capital World Investors |
13F
13D/G
Company
|
4.6%
from 13D/G
|
$196,085,426
29,575,479 shares
|
— | 31 Mar 2026 |
| PRIMECAP MANAGEMENT CO/CA/ |
13D/G
13F
Company
|
1.5%
|
$37,542,425
13,126,722 shares
|
$0 | 30 Jun 2025 |
| DIMENSIONAL FUND ADVISORS LP |
13F
Company
|
4.4%
|
$323,682,016
48,819,576 shares
|
— | 31 Mar 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC |
13F
Company
|
4.3%
|
$310,699,900
46,862,730 shares
|
— | 31 Mar 2026 |
| TWO SIGMA INVESTMENTS, LP |
13F
Company
|
4.2%
|
$308,054,570
46,463,736 shares
|
— | 31 Mar 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC |
13F
Company
|
4%
|
$293,526,165
44,272,423 shares
|
— | 31 Mar 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to buying over the last 12 months. Net value: +$48,963,499.
Buys
$54,690,000
Insiders: 3
Sells
$5,726,501
Insiders: 5
Net
+$48,963,499
Shares: +15,279,740
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 16,500,000
Shares: 1,220,260
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 81,741 | $0 | $608,970 | -$608,970 |
| 3-6 | 0 | 275,281 | $0 | $1,482,988 | -$1,482,988 |
| 6-9 | 16,500,000 | 823,238 | $54,690,000 | $3,504,143 | +$51,185,857 |
| 9-12 | 0 | 40,000 | $0 | $130,400 | -$130,400 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 23 reporting-owner rows connected to Transocean Ltd.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
23
Largest Forms 3/4/5 holder
Frederik W. Mohn
Net 12M change
+$48,963,498
Latest report
22 May 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Frederik W. Mohn | Director | $388,539,775 | +$18,230,000 | +4.9% | Mixed | 22 May 2026 |
| Perestroika (Cyprus) Ltd | Director | $388,231,073 | +$18,230,000 | +4.9% | Filing P/S | 24 Nov 2025 |
| Perestroika | Director | $388,231,073 | +$18,230,000 | +4.9% | Filing P/S | 24 Nov 2025 |
| Jeremy D. Thigpen | Executive Chair, Director | $17,985,569 | -$2,160,000 | -11% | Mixed | 01 Mar 2026 |
| Keelan Adamson | PRESIDENT AND CEO, Director | $10,814,889 | -$870,400 | -7.4% | Mixed | 01 May 2026 |
| Brady K. Long | EVP & Chief Legal Officer | $9,521,110 | -$1,574,220 | -14% | Mixed | 21 May 2026 |
| Mark-Anthony Lovell Mey | Evp & Cfo | $9,369,857 | Mixed | 01 Mar 2024 | ||
| Howard E. Davis | Evp, Cao & Cio | $8,256,412 | Mixed | 01 Mar 2024 | ||
| David A. Tonnel | Svp Chief Accounting Officer | $4,383,354 | Mixed | 01 Mar 2024 | ||
| Robert Thaddeus Vayda | EVP, Chief Financial Officer | $3,243,686 | -$128,700 | -3.8% | Mixed | 01 Mar 2026 |
| Roderick James Mackenzie | EVP, Chief Commercial Officer | $2,523,261 | -$993,182 | -28% | Mixed | 04 Mar 2026 |
| Jason Pack | SVP, Chief Accounting Officer | $1,977,412 | Mixed | 01 Mar 2026 | ||
| Vanessa C. L. Chang | Director | $343,919 | Mixed | 22 May 2026 | ||
| Victor Diane de Saint | Director | $277,815 | Mixed | 13 May 2022 | ||
| Chad C. Deaton | Director | $222,400 | Mixed | 22 May 2026 | ||
| Samuel J. Merksamer | Director | $217,231 | Mixed | 22 May 2026 | ||
| Domenic J. Dell'Osso Jr. | Director | $217,231 | Mixed | 22 May 2026 | ||
| Glyn Anthony Barker | Director | $217,231 | Mixed | 22 May 2026 | ||
| Margareth Oevrum | Director | $217,231 | Mixed | 17 May 2024 | ||
| Frederico F. Curado | Director | $217,231 | Mixed | 22 May 2026 |
Recent insider transactions for Transocean Ltd.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| William F. Lacey | RIG | Registered Shares | Tax liability | -25.4% | -20,934 | 61,419 | 26 May 2026 | Direct | ||
| Chad C. Deaton | RIG | Registered Shares | Tax liability | -9.37% | -20,932 | 202,421 | 26 May 2026 | Direct | ||
| Frederik Wilhelm Mohn | RIG | Registered Shares | Tax liability | -24.5% | -25,597 | 78,904 | 26 May 2026 | Direct | ||
| William F. Lacey | RIG | Registered Shares | Options Exercise | 82,353 | 82,353 | 22 May 2026 | Direct | |||
| William F. Lacey | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Chad C. Deaton | RIG | Registered Shares | Options Exercise | 58.4% | 82,353 | 223,353 | 22 May 2026 | Direct | ||
| Chad C. Deaton | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Frederik Wilhelm Mohn | RIG | Registered Shares | Options Exercise | 371.8% | 82,353 | 104,501 | 22 May 2026 | Direct | ||
| Frederik Wilhelm Mohn | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Vanessa C. L. Chang | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Vincent J. Intrieri | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Domenic J. Dell'Osso Jr. | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Frederico F. Curado | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Glyn Anthony Barker | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Samuel J. Merksamer | RIG | Restricted Units | Award | 30,435 | 30,435 | 22 May 2026 | Direct | |||
| Brady K. Long | RIG | Registered Shares | Sale | -6.77% | $608,970 | $7.45 | -81,741 | 1,125,438 | 21 May 2026 | Direct |
| Keelan Adamson | RIG | Registered Shares | Tax liability | -4.28% | -71,556 | 1,600,884 | 04 May 2026 | Direct | ||
| Keelan Adamson | RIG | Registered Shares | Options Exercise | 12.1% | 180,931 | 1,672,440 | 01 May 2026 | Direct | ||
| Roderick James Mackenzie | RIG | Registered Shares | Sale | -22.6% | $498,433 | $6.36 | -78,370 | 268,025 | 04 Mar 2026 | Direct |
| Robert Thaddeus Vayda | RIG | Registered Shares | Tax liability | -15.2% | -62,970 | 352,635 | 03 Mar 2026 | Direct | ||
| Keelan Adamson | RIG | Registered Shares | Tax liability | -7.9% | -127,878 | 1,491,509 | 03 Mar 2026 | Direct | ||
| Jason Pack | RIG | Registered Shares | Tax liability | -9.64% | -27,962 | 262,103 | 03 Mar 2026 | Direct | ||
| Brady K. Long | RIG | Registered Shares | Tax liability | -6.61% | -87,689 | 1,238,098 | 03 Mar 2026 | Direct | ||
| Jeremy D. Thigpen | RIG | Registered Shares | Tax liability | -8.59% | -245,556 | 2,614,548 | 03 Mar 2026 | Direct | ||
| Roderick James Mackenzie | RIG | Registered Shares | Tax liability | -15.4% | -62,886 | 346,395 | 03 Mar 2026 | Direct | ||
| Robert Thaddeus Vayda | RIG | Registered Shares | Options Exercise | 60.5% | 156,672 | 415,605 | 01 Mar 2026 | Direct | ||
| Keelan Adamson | RIG | Registered Shares | Options Exercise | 24.4% | 318,176 | 1,619,387 | 01 Mar 2026 | Direct | ||
| Jason Pack | RIG | Registered Shares | Options Exercise | 31.6% | 69,569 | 290,065 | 01 Mar 2026 | Direct | ||
| Brady K. Long | RIG | Registered Shares | Options Exercise | 19.7% | 218,177 | 1,325,787 | 01 Mar 2026 | Direct | ||
| Jeremy D. Thigpen | RIG | Registered Shares | Options Exercise | 27.2% | 610,979 | 2,860,104 | 01 Mar 2026 | Direct | ||
| Roderick James Mackenzie | RIG | Registered Shares | Options Exercise | 61.9% | 156,463 | 409,281 | 01 Mar 2026 | Direct | ||
| Robert Thaddeus Vayda | RIG | Registered Shares | Tax liability | -4.06% | -10,947 | 258,933 | 06 Feb 2026 | Direct | ||
| Jeremy D. Thigpen | RIG | Registered Shares | Tax liability | -5.89% | -147,729 | 2,362,028 | 06 Feb 2026 | Direct | ||
| Brady K. Long | RIG | Registered Shares | Tax liability | -3.51% | -40,294 | 1,107,610 | 06 Feb 2026 | Direct | ||
| Roderick James Mackenzie | RIG | Registered Shares | Tax liability | -9.54% | -26,665 | 252,818 | 06 Feb 2026 | Direct | ||
| Jason Pack | RIG | Registered Shares | Tax liability | -4.98% | -11,557 | 220,496 | 06 Feb 2026 | Direct | ||
| Keelan Adamson | RIG | Registered Shares | Tax liability | -3.82% | -51,709 | 1,301,211 | 06 Feb 2026 | Direct | ||
| Robert Thaddeus Vayda | RIG | Registered Shares | Options Exercise | 14.8% | 34,726 | 269,880 | 05 Feb 2026 | Direct | ||
| Robert Thaddeus Vayda | RIG | Restricted Units | Award | 239,740 | 239,740 | 05 Feb 2026 | Direct | |||
| Jeremy D. Thigpen | RIG | Registered Shares | Options Exercise | 17.5% | 373,534 | 2,509,757 | 05 Feb 2026 | Direct | ||
| Jeremy D. Thigpen | RIG | Restricted Units | Award | 407,332 | 407,332 | 05 Feb 2026 | Direct | |||
| Brady K. Long | RIG | Registered Shares | Options Exercise | 9.74% | 101,873 | 1,147,904 | 05 Feb 2026 | Direct | ||
| Brady K. Long | RIG | Restricted Units | Award | 233,290 | 233,290 | 05 Feb 2026 | Direct | |||
| Roderick James Mackenzie | RIG | Registered Shares | Options Exercise | 31.8% | 67,411 | 279,483 | 05 Feb 2026 | Direct | ||
| Roderick James Mackenzie | RIG | Restricted Units | Award | 204,939 | 204,939 | 05 Feb 2026 | Direct | |||
| Jason Pack | RIG | Registered Shares | Options Exercise | 14.4% | 29,211 | 232,053 | 05 Feb 2026 | Direct | ||
| Jason Pack | RIG | Restricted Units | Award | 76,629 | 76,629 | 05 Feb 2026 | Direct | |||
| Keelan Adamson | RIG | Registered Shares | Options Exercise | 10.7% | 130,738 | 1,352,920 | 05 Feb 2026 | Direct | ||
| Keelan Adamson | RIG | Restricted Units | Award | 712,831 | 712,831 | 05 Feb 2026 | Direct | |||
| Keelan Adamson | RIG | Registered Shares | Sale | -4.58% | $293,435 | $5.00 | -58,687 | 1,222,182 | 27 Jan 2026 | Direct |
* marks a reported price that did not pass the local price check.