CEO: Hosain Rahman

CEO rating: 64%

Number of ratings: 20

What employees are saying: "When things fail because of leadership, the teams get blamed, and the leaders get away with it. It's a dysfunctional place. Hosain has no idea of much of this because he's insulated by a level of people that are unable or refuse to give him the right information."

What it does: Jawbone is a hardware and electronics maker that makes music and fitness gear. It was founded in 1999.

Valuation: $3.3 billion.

CEO: Brian Chesky

CEO rating: 85%

Number of ratings: 74

What employees are saying: "Very smart people with huge egos and unfriendly, cliquey vibe. Young management cares a lot about PR and creating a glamorous company."

What it does: Founded in 2008, Airbnb lets people rent homes from each other for short stays as an alternative to traditional hotels.

Valuation: $10 billion; $794.8 million from Andreessen Horowitz, Founders Fund, Sequoia Capital, Greylock Partners and others.

CEO: Elon Musk

CEO rating: 82%

Number of ratings: 141

What employees are saying: "Elon changes his mind on what he wants on a regular basis." "Is it 'cool' to work for Elon? Sure it is. He has vision and courage to impact the future. There's a price to pay for working for a 'cool' company."

What it does: SpaceX makes, designs and launches rockets. It was founded in 2002.

Valuation: $4.8 billion.

CEO: Alexander Karp

CEO rating: 91%

Number of ratings: 69

What employees are saying: "The people are top notch. There's a lot of job satisfaction in working on hard problems where the solution actually makes a difference. Flat organization - individuals are encouraged to take responsibility and act with minimal hand-holding from above."

What it does: Founded in 2004, Palantir is a software and services company that specializes in data analysis. Its clients include government agencies like the CIA and FBI.

Valuation: $9 billion; $950 million raised from Founders Fund, Tiger Global Management, Glynn Capital Management and others.

CEO: Ben Silbermann

CEO rating: 92%

Number of ratings: 26

What employees are saying: "Whenever I hear Ben speak, I am amazed at his ability to inspire me and have a great sense of satisfaction working at the company."

What it does: Founded in 2008, Pinterest allows users to share and store photos, gifs and videos online by “pinning” content to personal pages.

Valuation: $5 billion; raised $762.5 million from Andreessen Horowitz, Rakuten and others.

CEO: Daniel Ek

CEO rating: 93%

Number of ratings: 22

What employees are saying: "The upper management is, I think, truly trying to reach out and understand what's happening behind the powerpoint slides. But I think they're too busy to realize that they just need to mix more with the rest of us to get a better feel of what is happening."

What it does: Music streaming service founded in 2006.

Valuation: $4 billion.

CEO: Jack Dorsey

CEO rating: 97%

Number of ratings: 91

What employees are saying: "I feel both challenged and supported in my work. I genuinely trust Jack as a leader as well as the rest of our execs."

What it does: Founded in 2009, Square helps small businesses accept credit cards as mobile payments. It also helps businesses with invoicing and mobile deposits.

Valuation: $6 billion; raised $590.5 million from KPCB, Khosla Ventures, Citi Ventures, Sequoia Capital and others.

CEO: Drew Houston

CEO rating: 99%

Number of ratings: 81

What employees are saying: "The founders (Drew and Arash) are very accessible and highly engaged in the day to day operations of the company - as someone else pointed out [on Glassdoor], they definitely 'walk the walk.'"

What it does: Founded in 2007, Dropbox stores files securely in the cloud so they can be accessed anywhere, from any device.

Valuation: $10 billion; $1.1 billion raised from Accel Partners, Benchmark Capital, Greylock Ventures and others.

CEO: Evan Spiegel

CEO rating: 100%

Number of ratings: 7

What employees are saying: "Amazing leadership team that inspires innovation and design thinking throughout the product and company culture."

What it does: Founded in 2012, Snapchat is a photo messaging app allows users to send photos and videos that get deleted after a set period of time.

Valuation: $10 billion; raised $163 million from Benchmark, SV Angel, Coutue Management, General Catalyst, Lightspeed Venture Partners and others.

CEO: Tom Reilly

CEO rating: 100%

Number of ratings: 26

What employees are saying: "The day I fell in love with the company was a day that Tom Reilly came down to chat with my team over lunch. In that conversation, our CEO told us that he wants Cloudera to be a place where people 'do what they think is best and ask for forgiveness later.'"

What it does: Big data. Founded in 2008.

Valuation: $4.1 billion.

CEO: Renaud Laplanche

CEO rating: 100%

Number of ratings: 40

What employees are saying: "I've yet to meet one person here who doesn't say it's the best job they've ever had."

What it does: A peer-to-peer loan company that was founded in 2006.

Valuation: $3.8 billion.

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