Founders: Allon Bloch (CEO), Ran Shaul, Israel Roth, Adam Singolda
Launched: 2016
Headquarters: New York City
Funding: $273.3 million
Valuation: $1.6 billion (PitchBook)
Key technologies: Artificial intelligence, machine learning
Industry: Health care
Previous appearances on Disruptor 50 List: 1 (No. 35 in 2020)

In just a few years, denizens of the internet have become accustomed to seeing and interacting with an emerging group of semi-sentient beings, ever-more-intelligent chatbots. These bots, powered by artificial intelligence and machine learning technology, provide product information, technical support, answers to billing questions and, in the case of the five-year old New York City-based start-up K Health, personalized medical advice.

Think of K as an improved version of WebMD. Instead of simply searching for symptoms, the K Health platform checks the combination of symptoms and personal information against the aggregate knowledge and experience of thousands of doctors and their clinical insights to provide a possible diagnosis, along with the resources to provide help for whatever is ailing the patient. 

This year, the company has been pursuing growth opportunities in helping parents, launching a new pediatrics platform in January. In February, K Health announced a partnership with Baltimore's school district, offering free access to its platform for the city's 80,000 students, with the hope that offering free health services to kids might help the city get more students back to school safely and keep them there.

K Health has added significant amounts of funding for the new efforts, raising a Series D round in November last year, and a Series E round less than two months later. The latest round brought the company to unicorn status, a reported valuation of $1.6 billion, according to PitchBook. The round was led by Valor Equity Partners and GGV Capital. Other investors include Mangrove Capital Partners and Comcast Ventures.

Disclosure: Comcast Ventures is a division of CNBC parent company Comcast.

—Contributed by David Spiegel

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