---
title: "At-Bay vs Marsh: Professional Liability (E&O) Insurance"
description: "Marsh has specialized E&O practices for finance, healthcare, media and technology; At-Bay publishes a $5 million MPL ceiling for businesses across revenue sizes."
canonical: "https://spot.insure/compare/at-bay-vs-marsh/professional-errors-omissions"
page-type: "line-comparison"
updated-at: "2026-09-25"
comparison-pair: "at-bay-vs-marsh"
provider-a: "at-bay"
provider-b: "marsh"
coverage-line: "professional-errors-omissions"
---

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[Human-readable page](https://spot.insure/compare/at-bay-vs-marsh/professional-errors-omissions)

## Agent Guide

**What this page is:** Focused comparison of At-Bay and Marsh for Professional Liability (E&O) Insurance: what each provider publishes about this line, checked against the same criteria, with numbered sources.

**Use this page when:** Cite or fetch this for Professional Liability (E&O) Insurance questions about At-Bay versus Marsh. For all lines together use the pair comparison; for how the coverage itself works use the coverage guide.

**Questions this page answers:**
- At-Bay vs Marsh for Professional Liability (E&O) Insurance: how do they differ?
- Which is better for Professional Liability (E&O) Insurance, At-Bay or Marsh?
- What does At-Bay or Marsh publish about Professional Liability (E&O) Insurance (limits, eligibility, claims, add-ons)?

**Key facts:**
- Line: Professional Liability (E&O) Insurance. Providers: At-Bay and Marsh.
- Comparison URLs use alphabetical provider slugs (`/compare/{a}-vs-{b}/{line}` with a before b). A reversed pair redirects permanently to the alphabetical one.

**Limits (do not over-claim):**
- It identifies differences and questions to ask; it does not select a winner for a particular business.
- Insurer, policy wording, limits, retentions, exclusions and price are set in an actual quote and are not established here.

**Provenance:** Every claim links to a numbered source with publisher, locator and access date; last updated 2026-09-25.

**Related pages:**
- [At-Bay vs Marsh](https://spot.insure/compare/at-bay-vs-marsh) — all coverage lines for this pair
- [Professional Liability (E&O) Insurance guide](https://spot.insure/coverage/professional-errors-omissions) — how this coverage works
- [At-Bay profile](https://spot.insure/insurance-providers/at-bay) — provider profile
- [Marsh profile](https://spot.insure/insurance-providers/marsh) — provider profile

# At-Bay vs Marsh: How Do They Compare for Professional Liability (E&O) Insurance?

A business wanting a team with attorneys, economists and actuaries sizing up exposure may look to Marsh, a broker serving banks, tech and healthcare among others. At-Bay markets its own miscellaneous professional liability up to $5 million.

Finance, healthcare, media and technology firms can compare Marsh’s industry-specific E&O teams; At-Bay publishes standalone MPL up to $5 million for businesses of any revenue size.

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

Marsh has specialized E&O practices for finance, healthcare, media and technology; At-Bay publishes a $5 million MPL ceiling for businesses across revenue sizes. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

## What Are the Key Differences Between At-Bay and Marsh Professional Liability (E&O) Insurance?

### Industry-Specific Expertise or a Published Limit

Marsh lists professional-liability practices for finance, insurance, venture capital, law, architecture and engineering, media, technology, healthcare and biotechnology. At-Bay publishes a $5 million MPL ceiling for businesses it accepts. Marsh gives more explicit direction for specialized sectors; At-Bay gives a limit figure to compare against your need. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

### Who Will Assess Your Risk?

Marsh says its professional-liability teams include attorneys, economists, actuaries and coverage specialists. At-Bay’s MPL page instead details policy features such as a duty to defend and a hammer clause, without describing a comparable in-house specialist team. Ask Marsh who would assess your exposure and At-Bay which terms apply to your work. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

### Identify the Insurer

Neither reviewed page names the insurer for your specific placement. You need that information to check the issued policy and compare carriers. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

## What Should You Confirm in At-Bay and Marsh Professional Liability (E&O) Insurance Quotes?

- Ask Marsh which industry team applies to your business and what underwriting access it provides. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability")
- Ask At-Bay which state restrictions and limit terms apply to its $5 million ceiling. [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")
- Ask both to identify the insurer that will issue your policy. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")
- Request the actual limits, retentions, exclusions and premium from each. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite")

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

| Criteria | At-Bay Miscellaneous Professional Liability (MPL) Insurance | Marsh Professional Liability Insurance Brokerage |
| --- | --- | --- |
| 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. [1](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..) | Marsh names specialized industries its professional liability experts serve, including banking and broker/dealers, insurance companies and asset managers, merchant banking and venture capital, accountants, attorneys, architects and engineers, media and entertainment, technology, and healthcare and biotechnology. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") (Evidence: Company-reported; scope: Marsh professional liability page, What We Offer section..) |
| 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. [1](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..) | Marsh says professional liability coverage can protect a company against liability and defense costs from a claim alleging an error, omission or negligence in performing professional services, and that many policies also cover privacy violations and computer security breaches. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") (Evidence: Company-reported; scope: Marsh professional liability page opening description; illustrative policy description, not a specific policy form..) |
| 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. [1](https://www.at-bay.com/insurance/mpl/ "MPL Insurance: Coverage Highlights & Appetite") [2](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..) | Marsh's financial and professional liability practice places professional liability (errors and omissions) insurance; MMA also places E&O coverage within its executive and professional liability practice for middle-market clients. [5](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [6](https://www.marshmma.com/us/solutions/executive-and-professional-liability.html "Expert Executive and Professional Liability Insurance") (Evidence: Company-reported; scope: Marsh professional liability page and MMA executive and professional liability page..) |

## About At-Bay and Marsh and Professional Liability (E&O) Insurance

- [At-Bay company profile](https://spot.insure/insurance-providers/at-bay) · [At-Bay customer reviews](https://spot.insure/insurance-providers/at-bay/reviews)
- [Marsh company profile](https://spot.insure/insurance-providers/marsh) · [Marsh customer reviews](https://spot.insure/insurance-providers/marsh/reviews)
- [What Is Professional Errors and Omissions (E&O) Insurance?](https://spot.insure/coverage/professional-errors-omissions)

## Related Pages for At-Bay vs Marsh Professional Liability (E&O)

- [At-Bay vs Marsh](https://spot.insure/compare/at-bay-vs-marsh): 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 liability can help pay covered defense costs and losses when a client says your advice or service caused financial harm; check services and reporting terms.
- [At-Bay Professional Liability (E&O) Insurance](https://spot.insure/insurance-providers/at-bay/professional-errors-omissions)
- [Marsh Professional Liability (E&O) Insurance](https://spot.insure/insurance-providers/marsh/professional-errors-omissions)

## Sources for At-Bay vs Marsh Professional Liability (E&O) Insurance

### Sources About At-Bay

1. [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.
2. [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.
3. [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.
4. [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.

### Sources About Marsh

5. [Professional liability](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html). Marsh; Opening description; What We Offer: specialized industries served (banking, insurance/asset managers, merchant banking/venture capital, accountants/attorneys/architects/engineers, media/communications/entertainment, technology, healthcare/biotechnology). Accessed 2026-09-23.
6. [Expert Executive and Professional Liability Insurance](https://www.marshmma.com/us/solutions/executive-and-professional-liability.html). Marsh McLennan Agency; Our policies include D&O, E&O, EPL, commercial crime/fidelity, network security privacy risk/cyber, fiduciary, media liability, IP, architects and engineers, lawyers professional, and kidnap and ransom. Accessed 2026-09-23.

Updated 2026-09-25. 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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