---
title: "At-Bay vs Chubb Professional Liability (E&O) Insurance"
description: "Chubb's Pro ERM is built for non-licensed professional-services firms specifically; At-Bay's MPL eligibility covers businesses of all revenue sizes without that restriction."
canonical: "https://spot.insure/compare/at-bay-vs-chubb/professional-errors-omissions"
page-type: "line-comparison"
updated-at: "2026-09-23"
---

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# At-Bay vs Chubb Professional Liability (E&O) Insurance

Chubb's Pro ERM is built for non-licensed professional-services firms specifically; At-Bay's MPL eligibility covers businesses of all revenue sizes without that restriction.

## Research Scope and Use

Use this comparison to evaluate At-Bay and Chubb for Professional Liability (E&O) Insurance against the same documented criteria. It identifies differences and questions to confirm; it does not select a winner for a particular business. Offering claims are what each provider publishes about this line unless marked otherwise. “Not found” describes the evidence reviewed, not proof that a feature is unavailable. Confirm the insurer, policy wording, limits, retentions, exclusions and cost in an actual quote.

## Summary

Chubb underwrites Pro ERM for non-licensed professional-services firms and covers 100% of worldwide defense costs without publishing a separate limit, while At-Bay sells MPL to businesses of any revenue size with a published limit ceiling of up to $5 million. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

## What Is At-Bay Insurance?

At-Bay offers Cyber, Tech E&O, and miscellaneous professional liability insurance through its disclosed insurance agency and surplus lines broker. Its Stance security services have policy eligibility conditions, with managed detection and response sold separately. [1](https://www.at-bay.com/insurance/ "Cyber, Tech E&O & Professional Liability Insurance") [2](https://www.at-bay.com/stance/ "At-Bay Stance")

[At-Bay profile](https://spot.insure/insurance-providers/at-bay)

## What Is Chubb?

Chubb is the marketing name for a global insurance group whose U.S. companies underwrite commercial property, casualty, cyber and financial-lines coverage, including technology-focused DigiTech ERM and small-business packages. Founders and finance teams typically work through an appointed agent, then receive a policy issued by a named Chubb-group insurer rather than by the Swiss holding company. [7](https://www.chubb.com/us-en/business-insurance/industries/technology.html "Insurance For Technology Companies") [8](https://www.chubb.com/us-en/terms-of-use.html "Terms Of Use") [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products")

[Chubb profile](https://spot.insure/insurance-providers/chubb)

## What Is Professional Errors and Omissions (E&O) Insurance?

Professional errors and omissions (E&O) insurance, also called professional liability insurance, addresses claims that professional services or advice caused a client financial loss. What's covered depends on the services actually scheduled in the policy, not the product label alone. [11](https://www.tdi.texas.gov/commercial/pl-faq.html "FAQ: Professional liability insurance") [12](https://www.iii.org/article/professional-liability-insurance "Professional liability insurance") [13](https://www.sba.gov/counseling/launch-your-business/#business-insurance "Get business insurance") [14](https://www.hiscox.com/documents/pl-sample-policy-wording.pdf "Professional Liability – US Direct Errors and Omissions Insurance")

## Key Differences in Professional Liability (E&O) Insurance

### Who Each One Is Eligible For

Chubb restricts Pro ERM to a specific category of buyer:

Chubb says Pro ERM is available to non-licensed professional-services firms of all sizes, naming examples including associations, consultants, business process administrators, event planners, interior and graphic design firms, marketing and PR firms, printers, staffing firms, travel agents and trustees. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Pro ERM Target Clients list..)

At-Bay's MPL eligibility runs differently, covering businesses of all revenue sizes without a comparable licensed-versus-non-licensed distinction. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

### How the Limit Is Disclosed

Chubb says Pro ERM covers 100% of defense costs for covered claims worldwide, but its reviewed page does not publish a separate liability limit or retention. At-Bay instead publishes an explicit limit ceiling for MPL up to $5 million, subject to state restrictions its page doesn't detail. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

### What Each Policy Automatically Extends

At-Bay's coverage highlights list automatic coverage for acquired subsidiaries as part of MPL. Chubb instead names automatic additional-insured status for clients when required by contract as a Pro ERM feature, a different kind of automatic extension. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products")

## What to Confirm in Professional Liability (E&O) Insurance Quotes

- Ask Chubb to confirm whether your business qualifies as "non-licensed" under Pro ERM's eligibility terms. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products")
- Ask At-Bay which insurer would issue a current MPL policy, since its product page does not name one. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")
- Ask Chubb for the actual liability limit and retention on your specific quote, since its page publishes defense-cost terms but not a standard limit. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products")
- Confirm which state restrictions apply to At-Bay's $5 million MPL ceiling for your business. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

## Offering Details

| Criteria | At-Bay Miscellaneous Professional Liability (MPL) Insurance | Chubb Pro ERM (Professional Enterprise Risk Management) |
| --- | --- | --- |
| Role in This Line | At-Bay markets MPL as one of its own named insurance products, sold through its disclosed producer, At-Bay Insurance Services LLC, with the product page directed at "properly licensed insurance professionals" submitting business rather than at direct retail buyers. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") [4](https://www.at-bay.com/licenses/ "Licenses") (Evidence: Company-reported; scope: Current MPL product page and license disclosures; this describes the distribution channel, not who bears the underwriting risk..) | Chubb underwrites professional errors and omissions coverage through Pro ERM, a single policy combining professional liability, media and cyber exposures for non-licensed professional-services firms. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Cyber Insurance Coverage & Products page, Professional Enterprise Risk Management section..) |
| Issuing Insurer | The current MPL product page does not name the insurer that issues the policy. A September 2023 press release named United Specialty Company in connection with MPL, but that historical reference does not establish the current issuing insurer for a new MPL quote. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") [5](https://www.at-bay.com/press_releases/at-bay-doubles-mpl/ "At-Bay Doubles Miscellaneous Professional Liability Appetite") (Evidence: Not found in reviewed sources; scope: Reviewed MPL page as of 2026-09-23 and the September 2023 press release; restates the existing provider fact that MPL's current issuer is unresolved, distinct from the August 2023 Cyber/Tech E&O transition to At-Bay Specialty Insurance Company paper..) | Not described in the reviewed sources. |
| Who It’s For | At-Bay says it provides primary MPL for businesses of all revenue sizes with limits up to $5 million, subject to state restrictions and eligibility requirements detailed in a separate MPL appetite guide. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") (Evidence: Company-reported; scope: Current MPL appetite paragraph; the linked appetite guide's specific eligibility requirements were not independently opened for this record..) | Chubb says Pro ERM is available to non-licensed professional-services firms of all sizes, naming examples including associations, consultants, business process administrators, event planners, interior and graphic design firms, marketing and PR firms, printers, staffing firms, travel agents and trustees. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Pro ERM Target Clients list..) |
| Coverage Features | At-Bay lists MPL coverage highlights including automatic coverage for acquired subsidiaries, claims-made-and-reported coverage, coverage for independent contractors, disciplinary-proceedings defense, a duty-to-defend contract, personal-injury coverage (including emotional distress), punitive damages where insurable, a professional-services definition written for each insured, and an 80/20 hammer clause. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") (Evidence: Company-reported; scope: Product-page coverage-highlights list; an 80/20 hammer clause is a settlement provision where the insurer pays 80% and the insured pays 20% of costs after the insured declines a recommended settlement. The issued policy and declarations control actual wording, limits and exclusions..) | Beyond the Cyber ERM base, Chubb says Pro ERM adds E&O coverage including personal injury from professional services, a broadened definition of professional services that expressly includes professional technology services, coverage for independent contractors performing duties on the insured's behalf, automatic additional-insured status for clients when required by contract, and coverage for professional disciplinary proceedings. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Pro ERM Product Features list; subject to the policy as issued..) |
| Limits and Retentions | At-Bay publishes an MPL limit ceiling of up to $5 million, with state restrictions that are not detailed on the product page itself. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") (Evidence: Company-reported; scope: Current appetite paragraph; this is an advertised ceiling, not a guaranteed available limit for any specific applicant..) | Chubb says Pro ERM includes coverage for 100% of defense costs for covered claims worldwide, but the reviewed page does not publish a separate liability limit or retention. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Pro ERM Product Features list..) |
| Risk Services | Not described in the reviewed sources. | Chubb says Pro ERM policyholders get access to legal counsel with extensive professional-liability experience, in addition to the general cyber-incident-response services shared with Cyber ERM. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Pro ERM Product Features list..) |
| How to Apply | At-Bay directs MPL submissions to underwriting by email or through automatic quotes on its Broker Platform, which At-Bay describes as a workflow of creating a quote, customizing limits and retentions, and binding the policy. [3](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") [6](https://www.at-bay.com/brokers/platform/ "Broker Platform") (Evidence: Company-reported; scope: Current submission instructions and the general broker-platform workflow description; MPL-specific automation details were not separately confirmed..) | Agents and brokers can quote Pro ERM through Chubb's Cyber Central or Marketplace quoting platforms. [9](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html "Cyber Insurance Coverage & Products") (Evidence: Company-reported; scope: Cyber Insurance Coverage & Products page quoting section..) |

## Full Comparison

- [At-Bay vs Chubb](https://spot.insure/compare/at-bay-vs-chubb): all coverage lines, business roles, service and claims.
- [What Is Professional Errors and Omissions (E&O) Insurance?](https://spot.insure/coverage/professional-errors-omissions): Professional E&O insurance addresses claims that a mistake in your advice or services caused a client financial loss.
- [At-Bay vs Chubb Cyber Insurance](https://spot.insure/compare/at-bay-vs-chubb/cyber)
- [At-Bay vs Chubb Tech E&O Insurance](https://spot.insure/compare/at-bay-vs-chubb/technology-errors-omissions)
- [Alliance Risk vs At-Bay Professional Liability (E&O) Insurance](https://spot.insure/compare/alliance-risk-vs-at-bay/professional-errors-omissions)
- [Alliance Risk vs Chubb Professional Liability (E&O) Insurance](https://spot.insure/compare/alliance-risk-vs-chubb/professional-errors-omissions)
- [At-Bay vs Beazley Professional Liability (E&O) Insurance](https://spot.insure/compare/at-bay-vs-beazley/professional-errors-omissions)
- [At-Bay vs CFC Professional Liability (E&O) Insurance](https://spot.insure/compare/at-bay-vs-cfc/professional-errors-omissions)
- [At-Bay vs Coalition Professional Liability (E&O) Insurance](https://spot.insure/compare/at-bay-vs-coalition/professional-errors-omissions)
- [At-Bay vs Corgi Professional Liability (E&O) Insurance](https://spot.insure/compare/at-bay-vs-corgi/professional-errors-omissions)

## Sources

### At-Bay

1. [Cyber, Tech E&O & Professional Liability Insurance](https://www.at-bay.com/insurance/). At-Bay; Product cards and agency disclosure. Accessed 2026-09-16.
2. [At-Bay Stance](https://www.at-bay.com/stance/). At-Bay; Real Protection Against Real Threats; Endpoint, Email, MXDR; footnotes 1 and 3–6. Accessed 2026-09-16.
3. [MPL Insurance: Coverage Highlights & Appetite](https://www.at-bay.com/insurance/mpl/). At-Bay; MPL Coverage Highlights list; MPL Appetite paragraph; Send us your submissions; "material on this page is intended for use solely by properly licensed insurance professionals". Accessed 2026-09-23.
4. [Licenses](https://www.at-bay.com/licenses/). At-Bay; Producer introduction; agency and surplus-lines footer naming At-Bay Insurance Services LLC. Accessed 2026-09-16.
5. [At-Bay Doubles Miscellaneous Professional Liability Appetite](https://www.at-bay.com/press_releases/at-bay-doubles-mpl/). At-Bay; September 28, 2023 release: final paragraph before Media Contacts. Accessed 2026-09-16.
6. [Broker Platform](https://www.at-bay.com/brokers/platform/). At-Bay; How it works: Create a quote, Customize your quote, Bind your policy, Manage renewals; FAQs. Accessed 2026-09-16.

### Chubb

7. [Insurance For Technology Companies](https://www.chubb.com/us-en/business-insurance/industries/technology.html). Chubb; Industry overview; Who we serve; Products and services: commercial package insurance (BOP, Benchmarq, Customarq), E&O/Cyber, Financial Lines, workers’ compensation, auto and umbrella; dedicated underwriting, claims and risk engineering. Accessed 2026-09-16.
8. [Terms Of Use](https://www.chubb.com/us-en/terms-of-use.html). Chubb; Acceptance of Terms identifying Chubb Group Holdings Inc.; surplus-lines producer restriction; products not available to all users or jurisdictions; Chubb Limited safe-harbor language; Internet Portals for Chubb Business. Accessed 2026-09-16.
9. [Cyber Insurance Coverage & Products](https://www.chubb.com/us-en/business-insurance/products/cyber-insurance/cyber-insurance-products.html). Chubb; Professional Enterprise Risk Management section: target clients and product features beyond Cyber ERM. Accessed 2026-09-23.
10. [Insurance for Software Product & System Developers](https://www.chubb.com/us-en/business-insurance/software-system-developers.html). Chubb; Financial-lines coverage solutions list for software and systems developers. Accessed 2026-09-23.

### Professional Liability (E&O) Insurance Guide

11. [FAQ: Professional liability insurance](https://www.tdi.texas.gov/commercial/pl-faq.html). Texas Department of Insurance; What’s professional liability coverage?; What types of damages…; What’s general liability insurance?; Do I need professional liability… if I have general liability…?; Is professional liability insurance required?; Can a client require…?; What’s the difference between occurrence policies and claims-made policies. Accessed 2026-09-16.
12. [Professional liability insurance](https://www.iii.org/article/professional-liability-insurance). Insurance Information Institute; Opening paragraphs (professional services/advice and E&O name); Claims not covered by general liability; What types of businesses need professional liability insurance?; What’s covered… and what’s not (claims-made versus occurrence, defense and judgments, non-financial/intentional limits, BOP/in-home exclusion). Accessed 2026-09-16.
13. [Get business insurance](https://www.sba.gov/counseling/launch-your-business/#business-insurance). U.S. Small Business Administration; Six common types of business insurance table. Accessed 2026-09-16.
14. [Professional Liability – US Direct Errors and Omissions Insurance](https://www.hiscox.com/documents/pl-sample-policy-wording.pdf). Hiscox Inc. specimen; About this Policy / Coverage for Claims Made Against You; I.A Insuring Agreement; I.B Defense; I.C Settlement; II.A Notice of Claims; II.C Optional Extended Reporting Period; III.A, III.K, III.M, III.R, III.S Exclusions; IV.A–B Limits and Deductible; VI.O Professional Services; VI.U Wrongful Act. Accessed 2026-09-16.

Updated 2026-09-23. Spot, a product of Tools for Enlightenment, publishes this research and works in the commercial insurance market. The comparison applies the same criteria to both providers. [Editorial policy](https://spot.insure/editorial-policy). To suggest a correction, [contact Spot](https://spot.insure/contact) with the page URL and supporting source.

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