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Rayner
Katharine Rayner
Rank #670
UNITED STATESMedia & EntertainmentMedia, automotive

Katharine Rayner

Net Worth
$6.05B
0% (24h)
Katharine Rayner, born in Atlanta, Georgia, in 1944 or 1945, is an American billionaire heiress and philanthropist. Her wealth stems primarily from her inheritance of a significant stake in Cox Enterprises, a media and automotive conglomerate founded by her grandfather, James M. Cox. As of March 25, 2026, her estimated net worth is $6.6 billion. Rayner is known for her philanthropic endeavors, particularly in support of cultural and educational institutions such as the New York Public Library and the Morgan Library & Museum. She resides in East Hampton, New York, where she is an avid gardener.

How to read Katharine Rayner's profile

Public net-worth figures are estimates. They combine observable inputs—typically listed equity, disclosed transactions, and market prices—with editorial judgment where filings are incomplete (for example, private holdings, debt, or cross-holdings). For Katharine Rayner, we anchor the narrative to Media and Media, automotive, then update the headline number as markets move. The chart on this page is meant to show trajectory, not a certified balance sheet.

When you see $6.05B alongside global rank #670, interpret it as our best synthesis of widely cited ownership and price signals—not a claim about cash on hand. Estimates can diverge from other publishers because of different treatment of options, trusts, charitable vehicles, or illiquid assets. We document the general approach in methodology and welcome corrections via corrections.

Country (UNITED STATES) and career milestones on this page are curated for reader context; they should be verified against primary sources when used for research. Editorial metadata for this profile is refreshed on a rolling basis, with deeper audits at least annually (last noted cycle: 2026).

Looking for depth? When available, the dossier and timeline sections below add long-form context beyond the headline number—prioritize those modules when evaluating claims about strategy, controversies, or philanthropic commitments.

The Full Dossier

Early Life and Family

Katharine Ann Johnson, later known as Katharine Rayner, was born in Atlanta, Georgia, in 1944 or 1945. She is the daughter of Anne Cox Chambers and Louis G. Johnson. Her mother, Anne Cox Chambers, was a prominent businesswoman and philanthropist, and the daughter of James M. Cox, the founder of Cox Enterprises. Katharine has a sister, Margaretta Taylor, and a half-brother, James Cox Chambers.

Rise to Success

Katharine Rayner inherited a significant stake in Cox Enterprises from her mother, Anne Cox Chambers, who distributed her 49% ownership in the company equally among her three children in 2015. This inheritance elevated Rayner to billionaire status. While Cox Enterprises is a major media and automotive conglomerate, neither Katharine nor her siblings have taken an active role in the company's operations.

Key Business Strategies

Katharine's wealth is primarily derived from her approximately 17% stake in Cox Enterprises. The company, founded in 1898, operates in various sectors, including media (Cox Communications, Cox Media Group) and automotive (Cox Automotive).

Philanthropy

Katharine Rayner is a dedicated philanthropist, focusing her giving on cultural and educational institutions. She serves on the boards of the New York Public Library and the Morgan Library & Museum. In 2017, she donated $15 million to the New York Public Library to enhance its research collections. In 2024, she pledged $10 million to the Morgan Library & Museum to endow the position of director, renaming it the Katharine J. Rayner Director. She has also contributed significantly to animal welfare causes, including a donation exceeding $5 million to the Animal Medical Center in New York City in 2019.

Career Timeline

2024

Pledge to Morgan Library & Museum

Pledged $10 million to endow the position of director, renaming it the Katharine J. Rayner Director.

2017

Donation to New York Public Library

Donated $15 million to enhance the library's research collections.

2015

Inheritance of Cox Enterprises Stake

Inherited a significant stake in Cox Enterprises, becoming a billionaire.

Philanthropic Impact

Education$15M

New York Public Library

Donation to enhance research collections.

Arts & Culture$10M

Morgan Library & Museum

Pledge to endow the position of director.

Animal Welfare$5M+

Animal Medical Center

Donation to support animal welfare.

Key Business Ventures & Holdings

CompanyStakeValue
Cox Enterprises17.00%$6.8M

Net Worth History

In-Depth Analysis

Early Life and Family

Katharine Ann Johnson, later known as Katharine Rayner, was born in Atlanta, Georgia, in 1944 or 1945. She is the daughter of Anne Cox Chambers and Louis G. Johnson. Her mother, Anne Cox Chambers, was a prominent businesswoman and philanthropist, and the daughter of James M. Cox, the founder of Cox Enterprises. Katharine has a sister, Margaretta Taylor, and a half-brother, James Cox Chambers.

Rise to Success

Katharine Rayner inherited a significant stake in Cox Enterprises from her mother, Anne Cox Chambers, who distributed her 49% ownership in the company equally among her three children in 2015. This inheritance elevated Rayner to billionaire status. While Cox Enterprises is a major media and automotive conglomerate, neither Katharine nor her siblings have taken an active role in the company's operations.

Key Business Strategies

Katharine's wealth is primarily derived from her approximately 17% stake in Cox Enterprises. The company, founded in 1898, operates in various sectors, including media (Cox Communications, Cox Media Group) and automotive (Cox Automotive).

Philanthropy

Katharine Rayner is a dedicated philanthropist, focusing her giving on cultural and educational institutions. She serves on the boards of the New York Public Library and the Morgan Library & Museum. In 2017, she donated $15 million to the New York Public Library to enhance its research collections. In 2024, she pledged $10 million to the Morgan Library & Museum to endow the position of director, renaming it the Katharine J. Rayner Director. She has also contributed significantly to animal welfare causes, including a donation exceeding $5 million to the Animal Medical Center in New York City in 2019.

Data Sources & Methodology

Figures for Katharine Rayner are synthesized from the sources below and cross-checked against our net worth methodology. Estimates may lag market moves; see corrections to report discrepancies.