Coverage description
A National Council on Compensation Insurance (NCCI) standard form. It records that the insured chose retrospective rating and that the workers compensation and employers liability premium is rated under the Large Risk Alternative Rating Option terms negotiated with the insurer.
Updated
What the form says
Key clauses from the original edition, which has not been revised, quoted as filed.
“This endorsement is issued because you chose to have the cost of the insurance rated retrospectively.”
WC 00 05 16
Why the endorsement is attached. The insured elected retrospective rating, so the final premium depends on losses during the policy rather than being fixed when the policy starts.
“applies only to workers compensation and employers liability insurance”
WC 00 05 16
Which coverage the option rates. Only the workers compensation and employers liability premium is rated under this option. The endorsement does not reach any other insurance.
“rated under the provisions of the Large Risk Alternative Rating Option that we have negotiated with you”
WC 00 05 16
Where the rating terms come from. The form sets out no formula, factors or schedule. The retrospective premium follows the Large Risk Alternative Rating Option provisions the insurer and insured negotiated, which sit outside this endorsement.
How the form has changed
Filed copies carry the original 01-10 edition, with no revision letter.
Editions
Edition dates as filed, newest first. Filing counts include every state submission that lists the edition.
| Edition | Filings | Companies | States | Filed | Document |
|---|---|---|---|---|---|
| OriginalLatest | 84 | 80 | 14 | Nov 2021 to Sep 2026 | View PDF |
What the filings show
- Edition in use: in the past 12 months, 33 companies filed the original edition.
- WC 00 05 03 (Retrospective Rating Plan Premium Endorsement One-Year Plan) is filed alongside it most often, in 74 of the same filings (88%).
Filed under
Data from admitted P&C filings with state insurance departments, submitted Nov 2021 to Sep 2026, excluding withdrawn and rejected filings. One filing can cover several affiliated companies.
Carriers filing this form
The 10 carrier groups with the most filings that include WC 00 05 16, out of 24 in total.
| Carrier | Filings | States | Editions, most filed first | Last filed |
|---|---|---|---|---|
| Brookfield Wealth Solutions Group4 group companies filed it, led by Argonaut Insurance Company and Argonaut-Midwest Insurance Company | 19 | 1 | Original | Jun 4, 2026 |
| AXA Insurance Group5 group companies filed it, led by Greenwich Insurance Company and XL Insurance America, Inc. | 6 | 2 | Original | Jun 23, 2026 |
| American Financial Group7 group companies filed it, led by Great American Alliance Insurance Company and Great American Assurance Company | 6 | 4 | Original | Jan 6, 2026 |
| Sompo Group2 group companies filed it, led by Sompo America Fire and Marine Insurance Company and Sompo America Insurance Company | 6 | 2 | Original | Jun 15, 2026 |
| RLI Insurance GroupRLI Insurance Company | 5 | 1 | Original | Aug 18, 2026 |
| THE Hanover Insurance Group6 group companies filed it, led by Allmerica Financial Alliance Insurance Company and Allmerica Financial Benefit Insurance Company | 5 | 1 | Original | Jun 23, 2026 |
| Arch Insurance Group2 group companies filed it, led by Arch Indemnity Insurance Company and Arch Insurance Company | 4 | 1 | Original | Apr 8, 2026 |
| Louisiana Workers Compensation GroupPrescient National Insurance Company | 4 | 1 | Original | Jul 2, 2025 |
| Tokio Marine Holdings Incorporated Group2 group companies filed it, led by Safety First Insurance Company and Safety National Casualty Corporation | 4 | 1 | Original | May 14, 2025 |
| Starr Group2 group companies filed it, led by Starr Indemnity and Liability Company and Starr Specialty Insurance Company | 3 | 1 | Original | Jun 25, 2025 |
States
Number of filings that include WC 00 05 16 in each state, Nov 2021 to Sep 2026. Darker states have more filings.
Often filed with
Standard-style form numbers that appear in the same filings most often.
- WC 00 05 03Retrospective Rating Plan Premium Endorsement One-Year Plan74 filings
- WC 00 05 04Retrospective Rating Plan Premium Endorsement Three-Year Plan73 filings
- WC 00 05 05Retrospective Rating Plan Premium Endorsement Wrap-Up Construction Project72 filings
- WC 00 05 11Retrospective Premium Endorsement-- Short Form72 filings
- WC 00 05 15Retrospective Rating Plan Premium Endorsement-- Flexibility Options72 filings
- WC 00 01 04Federal Employers' Liability Act Coverage Endorsement71 filings
- WC 00 01 06Longshoremen's and Harbor Workers' Compensation Act Coverage Endorsement71 filings
- WC 00 01 08Nonappropriated Fund Instrumentalities Act Coverage Endorsement71 filings
- WC 00 01 09Outer Continental Shelf Lands Act Coverage Endorsement71 filings
- WC 00 01 11Migrant and Seasonal Agricultural Worker Protection Act Coverage71 filings
Recent filings
Latest filings that include this form number. Filed copies open in FilingFocus.
| Submitted | Company | State | Editions | Tracking number |
|---|---|---|---|---|
| Sep 16, 2026 | ZNAT Insurance Company | CT | Original | ZICO-135090521 |
| Aug 18, 2026 | RLI Insurance Company | CO | Original | RLSC-135057018 |
| Jun 30, 2026 | American Casualty Company of Reading, Pennsylvaniaand 5 more | CO | Original | CNAB-135003197 |
| Jun 30, 2026 | Crestbrook Insurance Companyand 1 more | CO | Original | NWPP-135003409 |
| Jun 23, 2026 | Allmerica Financial Alliance Insurance Companyand 5 more | CO | Original | HNVX-134968029 |
| Jun 23, 2026 | AXA XL Insurance Company Americasand 3 more | CO | Original | XLAM-134996276 |
| Jun 15, 2026 | Sompo America Fire and Marine Insurance Companyand 1 more | CO | Original | SMPJ-134970923 |
| Jun 4, 2026 | Argonaut-Midwest Insurance Company | CO | Original | ARGN-134974739 |
| Jun 4, 2026 | Argonaut Insurance Company | CO | Original | ARGN-134974742 |
| Jun 4, 2026 | Rockwood Casualty Insurance Company | CO | Original | ARGN-134974764 |
| Apr 8, 2026 | Arch Insurance Company | CO | Original | AICO-G134902631 |
| Apr 8, 2026 | Arch Indemnity Insurance Company | CO | Original | AICO-G134902710 |
Most filed NCCI WC forms
- WC 00 00 01 Information Page
- WC 00 04 19 Part Five, Premium Amendatory Endorsement
- WC 00 00 00 Workers Compensation and Employers Liability Insurance Policy
- WC 00 04 21 Catastrophe (Other Than Certified Acts of Terrorism) Premium Endorsement
- WC 00 04 06 Premium Discount Endorsement
- WC 00 03 13 Waiver of Our Right to Recover From Others Endorsement
- WC 00 04 22 Terrorism Risk Insurance Program Reauthorization Act Disclosure Endorsement
- WC 00 03 08 Partners, Officers and Others Exclusion Endorsement
- WC 00 03 03 Employers Liability Coverage Endorsement
- WC 00 03 11 Voluntary Compensation and Employers Liability Coverage Endorsement
- WC 00 04 03 Experience Rating Modification Factor Endorsement
- WC 00 04 04 Pending Rate Change Endorsement