Charles Koch net worth is estimated at about $69.1 billion, based on the latest available Bloomberg Billionaires Index figure from late April 2026. That number is not cash sitting in a bank account. It is an estimate of his total wealth, built mostly from his large ownership stake in Koch Inc., one of the biggest privately held companies in the United States.
Koch’s fortune is harder to measure than the wealth of tech founders whose companies trade every day on the stock market. Koch Inc. is private, so researchers use company revenue, earnings estimates, comparable public companies, reported ownership stakes, debt, cash, donations, and private-market valuation methods.
This guide explains Charles Koch’s latest net worth, how it changed from 2025 to 2026, where his income comes from, what businesses he owns, his career timeline, public assets, ranking, controversies, and why different sources may report different numbers.
Quick Answer
Charles Koch is an American businessman, engineer, philanthropist, and the longtime leader of Koch Inc. His estimated latest net worth is about $69.1 billion.
His main source of wealth is his reported 38% stake in Koch Inc., the private industrial and investment conglomerate formerly known as Koch Industries.
Estimates vary because Koch Inc. is private, its divisions are valued by models, and different wealth trackers use different dates and methods.
Net Worth Snapshot Table
| Category | Details |
|---|---|
| Full name | Charles de Ganahl Koch |
| Known as / nickname | Charles Koch |
| Estimated latest net worth | About $69.1 billion |
| Estimated 2025 net worth | About $67.5 billion on Forbes’ 2025 billionaires list |
| Change in dollars | About +$1.6 billion |
| Change in percentage | About +2.4% |
| Main wealth source | Ownership stake in Koch Inc. |
| Country | United States |
| Industry | Diversified industrials, manufacturing, energy, technology, investments |
| Age | 90 |
| Birthday | November 1, 1935 |
| Birthplace | Wichita, Kansas, U.S. |
| Nationality | American |
| Last updated | April 29, 2026 |
| Confidence level | Medium-high |
| Reason for confidence level | His wealth is tracked by major billionaire indexes, and his ownership stake is publicly reported. Confidence is not “high” because Koch Inc. is privately held, so exact valuation details are not fully public. |
Basic Info
| Field | Details |
|---|---|
| Full name | Charles de Ganahl Koch |
| Nickname | Charles Koch |
| Age | 90 |
| Birthday | November 1, 1935 |
| Birthplace | Wichita, Kansas |
| Nationality | American |
| Profession | Businessman, engineer, philanthropist, author |
| Known for | Leading Koch Inc. since the 1960s and turning it into one of America’s largest private companies |
| Main industry | Diversified private business |
| Public status | Public billionaire, business leader, political and philanthropic donor |
Charles Koch is best known as the chairman and co-CEO of Koch Inc. He has led the company for more than five decades. Under his leadership, Koch grew from a smaller oil-related business into a broad private company active in refining, pipelines, paper products, packaging, electronics, glass, chemicals, software, agriculture, logistics, trading, real estate, investments, and technology.
Family and Personal Life
Charles Koch was born in Wichita, Kansas, to Fred C. Koch and Mary Robinson Koch. His father co-founded the business that later became Koch Inc. Charles was one of four sons in the Koch family.
His brothers were Frederick Koch, David Koch, and Bill Koch. David Koch worked closely with Charles for many years and was executive vice president of Koch Industries before his retirement. David died in 2019.
Charles Koch is married to Liz Koch. Koch’s official biography says they have been married for more than 50 years. They have two children, Elizabeth and Chase, and three grandchildren.
His son Chase Koch has held leadership roles connected to Koch and founded Koch Disruptive Technologies. His daughter Elizabeth Koch has been involved in publishing, storytelling, and philanthropic work.
Privacy note: Charles Koch is a public business figure, but many family details are not needed to understand his net worth. This article only includes family information that is public, relevant, and supported by reliable sources.
Education
Charles Koch studied at the Massachusetts Institute of Technology.
He earned:
| School | Degree / Study |
|---|---|
| MIT | Bachelor’s degree in general engineering, 1957 |
| MIT | Master’s degree in nuclear engineering, 1958 |
| MIT | Master’s degree in chemical engineering, 1959 |
His engineering background matters because Koch Inc.’s early growth was tied to oil refining, industrial processes, pipelines, chemicals, manufacturing, and technical operations. His education helped shape his focus on systems, efficiency, experimentation, and long-term reinvestment.
Koch has also written about ideas, economics, management, and what he calls Principle Based Management, formerly known as Market-Based Management.
Early Life and Background
Charles Koch grew up in Wichita, Kansas. His father, Fred Koch, was an engineer and entrepreneur who helped build an oil-refining and engineering business.
Koch’s own biography says his father did not want his sons to grow up without discipline. Charles worked on family property as a child, doing physical jobs such as farm work. This background is often used in Koch’s own public story to explain his focus on work, effort, and self-discipline.
His first major career step came when he joined the family business in 1961. At the time, the company was much smaller than it is now. It was linked to oil refining, engineering, and related assets.
The major turning point came after Fred Koch died in 1967. Charles took over leadership of the business and later helped rename and expand it. From there, the company grew across several industries through reinvestment, acquisitions, and private ownership.
Career Timeline
| Year | Milestone | What happened | Net worth impact |
|---|---|---|---|
| 1935 | Birth | Charles Koch was born in Wichita, Kansas. | No direct impact |
| 1957–1959 | MIT education | Earned one bachelor’s degree and two master’s degrees in engineering. | Helped prepare him for industrial leadership |
| 1961 | Joined family business | Returned to Wichita and joined the business founded by his father. | Beginning of career wealth creation |
| 1963 | Koch Engineering leadership | Became president of Koch Engineering, according to Bloomberg’s profile timeline. | Built operational experience |
| 1967 | Took over company | Became leader after Fred Koch’s death. | Put him in control of the company that created most of his fortune |
| 1968 | Company renamed | The business was renamed Koch Industries in honor of Fred Koch. | Brand and structure became clearer |
| 1970s | Expansion period | Koch expanded beyond its original oil-related roots. | Company value increased over time |
| 1976 | Cato Institute | Helped establish the Cato Institute, a libertarian policy organization. | More reputation impact than direct wealth impact |
| 1980 | Family control dispute | Brothers Bill and Frederick tried to remove Charles from control. | Created legal and ownership uncertainty |
| 1983 | Stock buyout | Bill and Frederick sold their Koch stakes back in a $1.1 billion transaction. | Strengthened Charles and David Koch’s control |
| 2000 | Legal dispute ends | Long-running family litigation over share value ended in favor of Charles and David. | Removed a major ownership overhang |
| 2005 | Georgia-Pacific deal | Koch Industries agreed to acquire Georgia-Pacific in a deal with $21 billion enterprise value. | Major expansion in paper, pulp, and building products |
| 2013 | Molex acquisition era | Koch expanded in electronics and components through Molex. | Diversified company value |
| 2020 | Infor acquisition completed | Koch completed acquisition of Infor, expanding software exposure. | Added software and enterprise technology exposure |
| 2023 | Co-CEO role | Charles became co-CEO while remaining chairman. | Leadership continuity |
| 2024 | Koch Inc. structure | Koch Industries changed its top-level name and structure to Koch Inc. | Reflected a more diversified company |
| 2025 | Forbes 400 recognition | Koch remained among America’s richest people. | Ranking visibility |
| 2026 | Latest wealth estimate | Bloomberg listed him at about $69.1 billion in late April 2026. | Shows modest rise from Forbes’ 2025 estimate |
Businesses and Ownership
Charles Koch’s wealth is centered on Koch Inc. Bloomberg reports that his fortune comes from a 38% stake in the company. Koch Inc. is closely held, meaning it is not traded on the public stock market.
Koch Inc. has many major businesses and investments. Its official materials list or describe companies and areas including:
| Business / Area | What it does | Ownership status |
|---|---|---|
| Flint Hills Resources | Refining, fuels, chemicals, pipelines, asphalt, related energy products | Koch company |
| Georgia-Pacific | Paper, pulp, packaging, tissue, building products | Koch-owned business |
| Guardian Industries | Glass and related products for buildings, vehicles, and industry | Koch company |
| INVISTA | Polymers, fibers, chemical intermediates, advanced materials | Koch company |
| Molex | Electronic components and connectivity solutions | Koch company |
| Infor | Enterprise software | Wholly owned by Koch after 2020 acquisition |
| Koch Ag & Energy Solutions | Fertilizer, agriculture, energy, methanol, related products | Koch company |
| Koch Engineered Solutions | Industrial technology and project services | Koch company |
| Koch Minerals & Trading | Commodities and trading | Koch company |
| Koch Investment Companies | Investments across private and public opportunities | Koch company |
| Koch Disruptive Technologies | Growth and venture-style investments | Koch-linked investment platform |
The biggest confirmed point is simple: Koch’s wealth is not mostly salary. It is ownership value.
Because Koch Inc. is private, its exact internal valuation is not fully public. Bloomberg’s valuation uses reporting on divisions, earnings estimates, revenue estimates, cash, investments, land, liabilities, and comparable company analysis. Forbes also uses private-company valuation methods and market indexes for large private stakes.
Net Worth 2025 vs Latest Net Worth
| Year / Date | Estimated net worth | Dollar change | Percentage change | Main reason for change |
|---|---|---|---|---|
| March 2025 | About $67.5 billion | — | — | Forbes 2025 billionaire list estimate |
| April 2026 | About $69.1 billion | About +$1.6 billion | About +2.4% | Updated private-company valuation and market movement tied to Koch Inc. |
Charles Koch’s estimated wealth rose by about $1.6 billion from Forbes’ 2025 estimate to Bloomberg’s late-April 2026 estimate. That is roughly a 2.4% increase.
The main reason is not a new salary, movie deal, sports contract, or public stock grant. It is the changing estimated value of Koch Inc. and related parent-company assets.
A private company like Koch is valued differently from Apple, Tesla, or Walmart. Wealth trackers must estimate the value of the underlying businesses, then apply ownership stakes, liabilities, cash, investments, and sometimes discounts. That is why the number can move even when there is no public stock ticker for Koch.
Wealth High and Low
Charles Koch’s recent wealth has moved within a fairly narrow range compared with many technology billionaires.
| Period | Estimated wealth level | Explanation |
|---|---|---|
| Recent high | Around the low-to-mid $70 billion range | Driven by strong valuation assumptions for Koch Inc. and its private businesses |
| Recent low | Around the high $60 billion range | Driven by valuation adjustments, private-market estimates, and changes in comparable industries |
| Latest available estimate | About $69.1 billion | Bloomberg’s late-April 2026 estimate |
Exact highs and lows are limited because Koch Inc. is private. Bloomberg’s visible one-year chart around late April 2026 showed his estimated wealth moving roughly between the high $60 billions and low-to-mid $70 billions.
The high is likely tied to stronger assumptions for Koch’s private assets, especially industrial, refining, materials, technology, and investment holdings. The low is likely tied to weaker valuation multiples, market changes, or adjustments to private-company estimates.
Income Sources
Charles Koch’s wealth is mostly ownership wealth, not annual pay. Public sources do not provide a confirmed yearly salary for him.
| Income source | Estimated value | Frequency | Reliability | Notes |
|---|---|---|---|---|
| Koch Inc. ownership stake | Main source; worth tens of billions | Long-term ownership | High | Bloomberg reports his fortune derives from a 38% stake |
| Private company value growth | Billions over time | Variable | Medium-high | Depends on valuation of Koch Inc. divisions |
| Dividends / distributions | Not publicly confirmed | Possible | Low-medium | Koch is private, so distributions are not fully public |
| Salary | Not reliably public | Annual if paid | Low | No reliable public salary figure found |
| Investments held through Koch parent | Large but not fully broken out | Variable | Medium | Bloomberg refers to cash, investments, land, and liabilities at the parent level |
| Real estate | Public details limited | Long-term | Low-medium | Some residence information is public, but a complete portfolio is not |
| Books | Small compared with ownership wealth | Occasional | Medium | Koch has authored business and philosophy books |
| Speaking / media | Not material to net worth | Occasional | Low | No evidence this is a major income source |
| Endorsements | No major public evidence | N/A | Low | Not a celebrity endorsement-based fortune |
| Crypto | No reliable public evidence | N/A | Low | Not part of supported wealth estimate |
| Sports contracts / touring / streaming | Not applicable | N/A | High | Koch is not an athlete or entertainer |
Property and Assets
Public property details for Charles Koch are limited, and this article avoids exact addresses or private-location details.
Koch’s official biography says he continues to reside in Wichita, Kansas, with his wife. That is relevant because Koch Inc. is also based in Wichita, and Koch has remained closely tied to Kansas.
The largest “asset” in his net worth is not a house, car collection, yacht, or jet. It is his ownership stake in Koch Inc.
Koch Inc. itself owns or controls major business assets, including factories, refineries, pipelines, manufacturing sites, offices, software businesses, trading operations, investments, and real estate. However, those are company assets, not necessarily personal assets that Charles Koch can sell as his own.
Reliable public sources do not provide a complete personal real estate portfolio for Charles Koch, and no exact private addresses should be published.
Lifestyle
Charles Koch is not widely known for a flashy celebrity lifestyle. Public coverage focuses more on his business leadership, political giving, philanthropy, and ideas than on luxury purchases.
Known public lifestyle themes include:
| Area | What is publicly known |
|---|---|
| Residence | Longtime Wichita, Kansas connection |
| Cars | No reliable public evidence of a major celebrity-style car collection |
| Private jets | Koch Inc. may use corporate aviation, but personal jet details are not central or fully public |
| Fashion | Not a major public topic |
| Travel | Likely business and philanthropy related, but detailed travel habits are private |
| Philanthropy | Major part of his public identity through Stand Together, Charles Koch Foundation, education, policy, poverty, addiction recovery, and related programs |
| Public spending habits | More associated with reinvestment, philanthropy, and policy work than public luxury |
Koch’s official biography says the company has historically reinvested a very large share of profits. That fits the way his wealth grew: by compounding company value rather than building a public luxury brand.
Philanthropy
Charles Koch is the founder of Stand Together, a philanthropic community connected to education, social entrepreneurship, criminal justice reform, addiction recovery, poverty reduction, free expression, and public policy.
He has also helped found or build organizations including the Cato Institute, Mercatus Center at George Mason University, Youth Entrepreneurs, Bill of Rights Institute, and Charles Koch Foundation.
His philanthropy is often praised by supporters for funding education, entrepreneurship, policy research, and community programs. It is also criticized by opponents who argue that parts of the Koch network advance free-market and deregulatory policies that serve political or business goals.
Both points matter. Philanthropy is a major part of Koch’s public life, but it is also one reason he remains controversial.
Controversies and Legal Issues
Charles Koch and Koch Inc. have been involved in several public controversies. The most relevant ones are business, environmental, family, and political issues.
Environmental settlements
In January 2000, the U.S. Department of Justice and the Environmental Protection Agency announced a settlement requiring Koch Industries to pay a $30 million civil penalty, improve leak-prevention programs, and spend $5 million on environmental projects. The case involved claims related to oil spills from pipelines and facilities in several states.
This was a company matter, not a personal criminal conviction of Charles Koch. Still, it affected Koch Industries’ public reputation and is an important part of the company’s history.
Family ownership dispute
In the 1980s, Charles Koch faced a major family fight over control and valuation of Koch stock. Brothers Bill and Frederick sold their stakes back to the company in 1983 for $1.1 billion, then later argued they had been underpaid. The long legal dispute ended in favor of Charles and David Koch.
This mattered financially because ownership control of Koch Industries was central to the family fortune.
Political influence criticism
Charles Koch has funded and supported libertarian, conservative, and free-market organizations for decades. Supporters say this reflects a consistent belief in limited government, individual freedom, and bottom-up social change. Critics say the Koch network has had outsized influence on tax, labor, climate, regulatory, and election debates.
The fair summary is that Koch’s public reputation is split. He is admired by many business and free-market supporters and criticized by many environmental, labor, and campaign-finance advocates.
Cato Institute dispute
Charles and David Koch were involved in a legal dispute connected to control of the Cato Institute. The matter was settled in 2012. It did not have a major direct effect on Charles Koch’s net worth, but it was important to his public policy network.
Ranking
| Ranking type | Latest available context |
|---|---|
| Billionaire status | Yes, billionaire |
| World ranking | Bloomberg listed Charles Koch at No. 25 with about $69.1 billion in late April 2026 |
| Forbes 2026 context | Forbes listed Charles Koch & family at No. 25 on its 2026 billionaires list |
| Country | United States |
| Industry | Industrial / diversified |
| State context | One of the richest people connected to Kansas |
| Wealth category | Private-company industrial billionaire |
Koch’s rank can change because other billionaires’ public stocks move daily, while Koch’s private-company valuation changes through models and periodic updates.
Comparison With Similar People
| Person | Estimated net worth | Main source of wealth | Industry | Who is richer? | Reason |
|---|---|---|---|---|---|
| Julia Koch & family | About $80B+ range in recent 2026 estimates | Inherited Koch Inc. stake | Diversified | Julia Koch & family | Larger inherited Koch stake is generally valued higher |
| Charles Koch | About $69.1B | Koch Inc. stake | Diversified industrials | — | Main subject |
| Jacqueline Mars | Roughly high-$40B to $50B range in public estimates | Mars Inc. | Candy, food, private company | Charles Koch | Koch Inc. stake is valued higher |
| Abigail Johnson | Varies by source, generally tens of billions | Fidelity | Finance | Charles Koch | Koch’s private-company stake is larger in most rankings |
| Phil Knight & family | Tens of billions | Nike | Apparel, sportswear | Charles Koch | Nike stake is large but below Koch’s latest estimate |
| Michael Bloomberg | Around $100B+ in many recent rankings | Bloomberg LP | Financial data, media | Michael Bloomberg | Bloomberg LP valuation is higher in major indexes |
| Jim Walton & family | Above $100B in major 2026 rankings | Walmart | Retail | Jim Walton | Walmart’s public-market value drives a higher estimate |
| MacKenzie Scott | Tens of billions | Amazon stock | Technology / investments | Charles Koch | Scott has donated large amounts and holds a smaller current fortune |
The closest comparison is Julia Koch & family because both fortunes are tied to Koch Inc. The main difference is that Julia Koch and her children inherited David Koch’s stake, while Charles Koch’s stake comes from decades of leadership and ownership.
Why Net Worth Estimates Differ
Net worth estimates differ for Charles Koch because his fortune is private and complex.
Key reasons include:
- Koch Inc. is not publicly traded.
There is no daily stock price that tells the market value of the company. - Private company valuations use models.
Analysts estimate value from revenue, earnings, comparable companies, assets, and debt. - Ownership stakes can be hard to track.
Bloomberg reports a 38% stake, while older public discussions often referenced higher voting or historical ownership percentages. - Donations can reduce economic ownership.
Reported donations of non-voting stock affected how some trackers calculate his personal fortune. - Debt and cash are not always fully public.
Private companies do not disclose all details like public companies do. - Taxes are not the same as net worth.
A billionaire’s listed fortune is usually pre-tax estimated asset value. - Net worth is not cash.
Charles Koch cannot instantly turn a private-company stake into cash without major legal, tax, and business consequences. - Different sources use different dates.
Forbes’ annual list may use a fixed date, while Bloomberg updates on business days. - Illiquidity matters.
A private company stake is harder to sell than public stock. - Private assets may be discounted.
Some models may value private shares lower because they are not easily sold.
How We Estimated Net Worth
This article uses a transparent estimate, not an exact claim.
The latest working estimate is based mainly on:
| Factor | How it affects the estimate |
|---|---|
| Bloomberg Billionaires Index | Gives the latest available estimate of about $69.1 billion |
| Forbes 2025 billionaire list | Gives a 2025 comparison point of about $67.5 billion |
| Reported Koch Inc. ownership | Bloomberg says Koch’s fortune derives from a 38% stake |
| Koch Inc. revenue scale | Public sources say annual revenue has exceeded $125 billion |
| Private-company structure | Requires model-based valuation, not a simple stock-price calculation |
| Koch subsidiaries | Georgia-Pacific, Flint Hills, Molex, INVISTA, Infor, Guardian, and other businesses support value |
| Cash, investments, land, liabilities | Bloomberg includes parent-level assets and liabilities in its analysis |
| Stock donations | Reported non-voting stock donations reduce economic ownership in some estimates |
| Company growth | Koch says it has invested heavily in growth and improvements since 2003 |
The best estimate for April 2026 is therefore about $69.1 billion, with a reasonable public-source range around the high $60 billions to low $70 billions.
Latest Updates
| Update type | Latest available information |
|---|---|
| Most recent wealth change | Bloomberg showed Charles Koch at about $69.1 billion in late April 2026, with a small year-to-date decline at that moment |
| Most recent business update | Koch Inc. continues to operate as a diversified private company after its 2024 name and structure change |
| Most recent ranking update | Forbes listed Charles Koch & family at No. 25 on its 2026 billionaires list |
| Most recent career update | Koch’s official site lists him as chairman and co-CEO |
| Most recent public company context | Koch says the company has about 120,000 employees worldwide and operations in more than 50 countries |
| Date of latest available information | April 29, 2026 |
FAQ
What is Charles Koch’s net worth?
Charles Koch’s net worth is estimated at about $69.1 billion based on the latest available Bloomberg figure from late April 2026.
How did Charles Koch get rich?
He got rich mainly by owning and leading Koch Inc., the private conglomerate that grew from his father’s oil-related business into a huge diversified company.
What is Charles Koch’s salary?
A reliable public salary figure for Charles Koch is not available. His wealth comes mostly from ownership, not salary.
How much does Charles Koch make per year?
His annual income is not publicly confirmed. His estimated wealth can rise or fall by billions depending on the valuation of Koch Inc.
Is Charles Koch a billionaire?
Yes. Charles Koch is a billionaire many times over and ranks among the richest people in the world.
What businesses does Charles Koch own?
His wealth is tied to Koch Inc., which includes or controls businesses such as Flint Hills Resources, Georgia-Pacific, Guardian Industries, INVISTA, Molex, Infor, Koch Ag & Energy Solutions, Koch Engineered Solutions, Koch Minerals & Trading, and investment operations.
What is Charles Koch’s biggest income source?
His biggest wealth source is his ownership stake in Koch Inc.
How much was Charles Koch worth in 2025?
Forbes’ 2025 billionaires list put Charles Koch & family at about $67.5 billion.
Why do Charles Koch net worth estimates differ?
They differ because Koch Inc. is private, ownership details are complex, and each wealth tracker uses its own valuation method and date.
Who is richer, Charles Koch or Julia Koch?
Julia Koch & family are generally ranked slightly richer because they inherited David Koch’s large Koch Inc. stake.
Does Charles Koch own real estate?
He is publicly connected to Wichita, Kansas, but a complete personal real estate portfolio is not reliably public. His main asset is his Koch Inc. stake.
What is Charles Koch’s latest ranking?
Bloomberg listed Charles Koch at No. 25 in late April 2026, and Forbes also listed Charles Koch & family at No. 25 on its 2026 billionaires list.
Conclusion
Charles Koch net worth is best estimated at about $69.1 billion in 2026. The main reason he is so wealthy is his large stake in Koch Inc., a private company with major businesses in energy, manufacturing, paper products, electronics, software, trading, agriculture, and investments.
His estimated fortune rose by about $1.6 billion, or roughly 2.4%, compared with Forbes’ 2025 estimate of $67.5 billion. Still, the number should be treated as an estimate, not exact cash. Koch’s wealth depends on private-company valuation models, ownership assumptions, debt, cash, investments, and market comparisons.
The clearest takeaway is that Charles Koch remains one of America’s richest business figures because he built and kept control of one of the country’s largest private companies.
Source Notes
| Source name | Page title | What it was used for | Link |
|---|---|---|---|
| Bloomberg | Bloomberg Billionaires Index — Charles Koch | Latest net worth, rank, ownership stake, business valuation notes, age, industry, methodology, career milestones | |
| Forbes | Charles Koch & family profile | 2026 billionaire ranking context | |
| Forbes Australia | Forbes World’s Billionaires List 2025: Top 200 | 2025 net worth comparison of $67.5 billion | |
| Forbes | Real-Time Billionaires methodology | Private-company valuation method and market-index context | |
| Koch Inc. | Charles Koch leadership profile | Official role, company scale, education, family, philanthropy, 2023 co-CEO role, 2026 company context | |
| CharlesKoch.com | Biography — Lasting Contributions | Early life, family background, 1960s career, reinvestment, Koch Inc. structure, philanthropy | |
| Koch Inc. | Companies | Koch company and subsidiary context | |
| Bloomberg | Koch Changes Company Name to Reflect Its Diversification | 2024 Koch Inc. name and structure change | |
| SEC archive | Koch Industries press release on Georgia-Pacific acquisition | Georgia-Pacific acquisition value and deal terms | |
| Forbes | Koch company overview | Koch revenue scale and private-company context | |
| EPA | Koch Industries Oil Spills Settlement | Environmental settlement details | |
| U.S. Department of Justice | Koch Industries to Pay Record Fine for Oil Spills | Oil-spill settlement and penalty details | |
| Cato Institute | Koch v. Cato Settlement | Cato dispute settlement context | |
| Celebrity Net Worth | Charles Koch Net Worth | Cross-check of public net-worth estimates and simple profile style | |
| Wikipedia | Charles Koch | Cross-check for birthday, birthplace, education, siblings, and public biography details | |
| Forbes | Julia Koch & family profile | Comparison table and Koch family wealth context | |
| Forbes | Jim Walton & family profile | Comparison table ranking context | |
| Forbes | Jacqueline Mars profile | Comparison table ranking context |
