1. David and Bill Koch

David and Bill Koch’s father, Fred Koch, started Koch Industries in 1940. The hugely successful conglomerate, which has generated over US$100 billion in revenue, produces fertiliser, Dixie paper cups, Quilted Northern toilet paper and refines crude oil.

The Koch twins engaged in a decades-long battle over control of the board of their father’s company. Despite their drawn-out conflict, Bill expressed grief for his twin brother when he died in 2019, nearly three decades after being diagnosed with prostate cancer.

2. Mary-Kate and Ashley Olsen

The Business of Fashion reported in 2019 that, according to market-source estimates, The Row was bringing in between US$100 million and US$200 million annually.

3. Tyler and Cameron Winklevoss

Forbes reported that Cameron and Tyler Winklevoss each have a net worth of US$1.5 billion as of May 2023.

In 2014, they co-founded Gemini, which processes around US$200 million in trades every day, according to Forbes. Tyler is the CEO of the company while Cameron serves as its president.

4. Scarlett and Hunter Johansson

5. Scott and Mark Kelly

Former Nasa astronauts Scott and Mark Kelly are an undeniably accomplished duo. Mark has served as a US senator since 2020.

Born in Orange, New Jersey, Mark and Scott Kelly are the world’s first identical twin astronauts. The twins became Nasa astronauts in 1996. They went on a total of seven missions to space, although they never went together.

Mark Kelly retired from the position in 2011. During his 15-year run as an astronaut, he spent over 50 days total in space and travelled over 20 million miles.

Scott retired from the agency in 2016, and the following year he published a memoir, Endurance: A Year in Space, a Lifetime of Discovery, in which he shares details about his life as an astronaut.

6. Jenna Bush Hager and Barbara Pierce Bush

In 2017, Jenna and Barbara co-authored a No. 1 New York Times bestseller, Sisters First: Stories from Our Wild and Wonderful Life, a memoir in which they share details about their time in the White House and their relationship.

7. Markieff and Marcus Morris

Not only are the Marcus twins identical, but they both have incredible athletic abilities that they’ve each taken to the NBA.

Earlier this year, Markieff Morris was traded to the Dallas Mavericks from the Brooklyn Nets, while Marcus Morris plays for the LA Clippers. Markieff had previously signed a one-year, US$2.9 million contract with the Nets, while in 2020 Marcus reportedly agreed to a four-year, US$64 million contract with the Clippers.

Although they now play for different teams, the Morris brothers started playing basketball together in Philadelphia in high school.

8. Pavol and Peter Hochschorner

The Hochschorner twins are the first Slovakian athletes to win three gold medals in the Olympics. They won gold at three consecutive summer Olympics: Sydney in 2000, Athens in 2004 and Beijing in 2008. Four years later, in London, they earned a bronze medal.

Between 2000 and 2015, the Slovak Canoe Association named Peter and Pavol Canoeists of the Year nine times. They were voted Slovakia’s Athletes of the Year in 2009 and 2011.

In the span of four years – between 2000 and 2004 – they won the ICF Canoe Slalom World Cup multiple times, and they won an ECA European Championship as well as the World Championships.

9. Tia and Tamera Mowry

After acting alongside one another on children’s programmes like Sister, Sister and Twitches, the Mowry twins were the subject of a reality show, Tia & Tamera.

By 2015, Tia had her own Cooking Channel series, Tia Mowry at Home, on which she taught recipes to celebrity guests. The show and her interest in cooking spawned two cookbooks and a cookware line available in stores including Target, Amazon and Walmart. She also shares cooking videos on her YouTube channel, which has nearly one million subscribers. The sisters have also worked on books together.

10. Dylan and Cole Sprouse

The Sprouse twins are best known for their 2005 acting debut on The Suite Life of Zack & Cody and, later, their roles on its spin-off, The Suite Life on Deck. TV Guide reported that, as children and teenagers, the Sprouse twins each made around US$20,000 per episode.

Cole is now best known for his role as Jughead Jones on the hit show Riverdale, and he has won three Teen Choice Awards for his performance.

In 2020, Dylan played the role of Trevor in After We Collided. He now owns a successful meadery in Brooklyn, New York, which brought in over US$1 million in revenue in 2019, its second year of business, according to Forbes.

Both twins made Forbes’ 30 Under 30 list in 2020.

11. Ashton and Michael Kutcher

In addition to starring in films Kutcher has also had a lucrative TV career on shows including That ‘70s Show and The Ranch. Forbes reported he earned US$26 million in 2014, when he was among Hollywood’s top 100 earners for the year.

While his twin brother is not an actor, he has made a successful career out of advocacy. Michael, who has cerebral palsy, delivers motivational speeches throughout the country. He has spoken at Capitol Hill, the Centers for Disease Control and the National Institute of Health.