THE $20 BILLION CLUB: Meet the 5 most valuable startups in the world

Valuation: $15 billion, but $500 million in new funding could bump up its valuation to $20 billion

CEO: Alexander Karp

Founded: 2004

What it does: Palantir is a software and services company that specializes in data analysis. Some of its biggest clients are government agencies like the CIA and the FBI.

Total funding: ~$1.5 billion

Notable investors: Founders Fund, Tiger Global Management, Glynn Capital Management, Jeremy Stoppelman

Valuation: $24 billion

CEO: Brian Chesky

Founded: 2008

What it does: Through its app and website, Airbnb provides a marketplace for people to rent out rooms or their entire homes to other people.

Total funding: ~$1.8 billion, pending a fresh $1 billion round of funding

Notable investors: SherpaCapital, T. Rowe Price, Founders Fund, CrunchFund, Sequoia Capital, Andreessen Horowitz, DST Global, General Catalyst Partners, SV Angel, Greylock Partners

Valuation: $41.2 billion, though a new round of funding could raise its valuation to $50 billion.

CEO: Travis Kalanick

Founded: 2009

What it does: Uber's taxi-hailing app connects its users with drivers of private vehicles under contract with Uber. It offers different types of cars, from full-size luxury cars to smaller vehicles.

Total funding: $5.9 billion

Notable investors: Benchmark Capital, Menlo Ventures, Google Ventures, KPCB

Valuation: $46 billion

CEO: Jun Lei

Founded: 2010

What it does: Xiaomi is a Chinese electronics brands that manufactures smartphones. The company's smartphones are considered among the best that run Android, and the company has hardcore loyalists as Apple does in the US.

Total funding: $1.4 billion

Notable investors: Digital Sky Technologies, Hopu Investment Management Company, DST Global, IDG Capital Partners, Qualcomm Ventures, Morningside Group

SpaceX, Elon Musk's space exploration company, designs, builds, and launches vehicles for space exploration. SpaceX has raised $1.2 billion at a $12 billion valuation.

Flipkart is an India-based e-commerce site specializing in electronics and content like books and music. It has a $15 billion valuation and has raised $2.5 billion in funding.

Virtual pinboard Pinterest has raised $1.3 billion at an $11 billion valuation.

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