What Ivins, Phillips & Barker does

Ivins, Phillips & Barker is a Washington, D.C.-based boutique law firm founded in 1935 that practices exclusively in federal income tax, employee benefits and compensation, and estate planning. Organized into three practice groups (Tax, Benefits & Compensation, and Estate Planning), the firm delivers high-end advisory, controversy, litigation, and legislative/regulatory advocacy services to Fortune 500 corporations, prominent families, and tax-exempt organizations. Its core technology is its attorneys' specialized knowledge: partners include former U.S. Tax Court and Court of Claims judges, Treasury Department officials (notably former Assistant Secretary for Tax Policy Eric Solomon and former IRS Associate Chief Counsel Robert Wellen), and Congressional Joint Committee on Taxation staff, positioning the firm as a regulatorily influential advisor that has shaped — not merely interpreted — U.S. tax law.

The firm generates revenue through professional services billed on engagement or retainer terms to enterprise and high-net-worth clients. Notable engagements include advising H.J. Heinz on the approximately $60 billion acquisition of Kraft (2015), securing the largest pension funding waivers ever granted by the IRS and PBGC for Delphi Corporation (2007), and prevailing in Dominion Resources v. United States (2012), the first case to apply the APA's arbitrary-and-capricious standard to invalidate a tax regulation. Marquee clients span manufacturing (Heinz, GM, Milliken, du Pont family), energy (Dominion Resources, Carolina Power & Light), technology (Xerox, Eastman Kodak), and insurance (Platinum Supplemental Insurance). Distribution is direct and partner-led; the firm does not advertise pricing or maintain a public rate card.

IPB is a privately held partnership (legal entity: Ivins, Phillips & Barker, Chartered) with 101-250 employees, a single Washington office at 1717 K Street NW, and over 44% women equity partners as of 2025. Growth has been driven by selective lateral hiring of senior government alumni, sustained recognition in Chambers USA, Best Lawyers, Best Law Firms, and Legal 500, and selective expansion into international advisory work — including 2025 engagements advising European football clubs at the FIFA Club World Cup. The firm does not disclose revenue, maintain external funding, or operate a technology platform.

Name

Ivins, Phillips & Barker

Legal name

Ivins, Phillips & Barker, Chartered

Website

https://ipbtax.com

Company type

Private

Founded year

1935

Operating status

Operating

Headcount range

101–250 employees

Short description

Ivins, Phillips & Barker is a Washington, D.C. boutique law firm, founded in 1935, that practices exclusively in federal tax, employee benefits, and estate planning for Fortune 500 corporations, prominent families, and tax-exempt organizations, staffed by former Treasury, IRS, and Tax Court officials.

Ownership category

akta.pro rank

Product category

Tax Law Services

NAICS

Offices of Lawyers (541110)

SIC

Services-Legal Services (8111)

akta.pro primary industry

Trust & Estate Tax Planning & Compliance (FSAEAKAE)

akta.pro secondary industries

Estate Planning & Trust Structuring Advisory (FSAEAKAC), Family & Private Client (Trusts & Estates) Law (BPAHAAAK), Litigation Support & Expert Witness Services (BPAHALAG), Estate Administration & Probate Services (FSAAANAE)

Keywords

• Federal tax law
• Employee benefits counsel
• Estate planning services
• Tax controversy litigation
• ERISA compliance

Headquarters

HQ city

Washington

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Infrastructure, Technology or R&D, Others

Revenue model

1. Legal Services: Ivins, Phillips & Barker generates revenue through legal services in federal tax, employee benefits, and estate planning. The firm serves Fortune 500 corporations and prominent families, indicating high-value professional services engagements.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels5 records

Core offering

Ivins, Phillips & Barker is a Washington, D.C. boutique law firm that has practiced exclusively in federal tax, benefits and compensation, and estate planning since 1935. The firm delivers legal counsel across three practice areas—Tax (including federal tax policy & advocacy, tax planning, international tax, tax accounting, tax controversies, and arbitration/litigation support), Benefits & Compensation (retirement plans, executive compensation, health and welfare, M&A, payroll tax, plan investments, vendor contracting, and ERISA litigation), and Estate Planning (estate administration, gift and estate tax planning, wills and trusts, family-owned businesses, exempt organizations, and charitable giving). Engagements are partner-led and serve Fortune 500 corporations, high-net-worth families, and charitable foundations on complex U.S. federal tax matters.

Product overview

Ivins, Phillips & Barker is a specialized tax and benefits law firm organized into three main practice areas: Tax (including Federal Tax Policy & Advocacy, Tax Planning & Advisory Services, International Tax, Tax Accounting, Tax Controversies/Litigation, and Arbitration & Litigation Support), Benefits & Compensation (covering Retirement Plans, Executive Compensation, Health & Welfare, M&A, Payroll Tax, Plan Investments, Vendor Contracting/HR Outsourcing, and ERISA Litigation), and Estate Planning (including Estate Administration, Gift & Estate Tax Planning, Income Tax Planning, International Planning, Wills & Trusts, Family-Owned Businesses, and Exempt Organizations & Charitable Giving). The firm is a single-unified-service law firm offering complementary practice areas that share common technical foundations in federal tax law and employee benefits regulations.

Differentiator

Problem solved

Functional benefit

Products and services

• Tax Practice Comprehensive federal tax legal services covering policy advocacy, planning, international tax, tax accounting, IRS audit defense, appeals, tax litigation, and arbitration support, delivered to corporations and high-net-worth clients.
• Benefits & Compensation Practice Employee benefits legal services covering retirement plans, executive compensation, health and welfare plans, mergers and acquisitions, payroll tax, plan investments, vendor contracting, HR outsourcing, and ERISA litigation for corporate clients.
• Estate Planning Practice Estate and wealth transfer planning services covering estate administration, gift and estate tax planning, income tax planning, international planning, wills and trusts, family business planning, and charitable giving for individuals, families, and exempt organizations.

Named customers11 records

Segments3 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Scale indicators1 record

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• Vinson & Elkins: Large energy and corporate-focused firm whose tax practice competes for federal tax controversy and benefits work from the same Fortune 500 corporate base.
• Skadden Arps Slate Meagher & Flom: AmLaw 50 firm with leading tax, executive compensation, and benefits practices serving large corporate clients on transactional and controversy matters that overlap with IPB.
• Gibson Dunn: AmLaw 10 firm with nationally recognized tax and benefits practice; competes for sophisticated corporate tax planning, controversy, and ERISA matters for shared Fortune 500 clients.
• McDermott Will & Emery: Globally recognized law firm with a top-tier tax and benefits practice. Larger and broader than IPB, but competes for many of the same sophisticated federal tax and ERISA matters.
• Akin Gump Strauss Hauer & Feld: Large international law firm with a strong tax and policy practice in DC and a comparable elite-client roster; competes on federal tax policy advocacy and complex tax planning.
• Wachtell Lipton Rosen & Katz: Elite New York-based firm with premier M&A and benefits practices; competes at the high end of the same market as IPB, particularly on large-deal employee benefits and tax structuring.

Direct peers

• Miller & Chevalier Chartered: DC-headquartered chartered tax boutique with strong overlap in federal tax planning, tax litigation, and employee benefits work, serving comparable Fortune 500 and high-net-worth clients.
• Sutherland Asbill & Brennan: Significant tax controversy and benefits practice at a firm of broadly comparable size; substantial overlap with IPB in federal tax, employee benefits, and energy/retirement plan matters.
• Caplin & Drysdale: Washington, DC-based tax boutique chartered firm with comparable practice depth in federal tax, tax controversies, and exempt organizations. Closest structural and strategic analog to IPB.
• Steptoe & Johnson: DC-based law firm with a comparable specialized tax, employee benefits, and policy advocacy practice, including former government attorneys serving Fortune 500 clients.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/ivins-phillips-&-barker

Revenue estimate

Valuation estimate

Number of profiles

Profiles10 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Ivins, Phillips & Barker