Google is ditching one of its highest-profile robotics businesses, selling it off to a Japanese tech giant.

Japan's SoftBank (SFTBF) announced Friday that it's buying robot maker Boston Dynamics from Google's parent Alphabet (GOOG), saying the deal will help it in its aim to be at the forefront of "the next wave of smart robotics."

Boston Dynamics has repeatedly made headlines with its eye-catching robots, which can run, jump and climb stairs. Its CEO has described one of them as "nightmare inducing."

SoftBank's billionaire CEO Masayoshi Son has made no secret of his enthusiasm for robots: he's widely quoted as saying they will outnumber humans in 30 years. SoftBank is one of the companies behind Pepper, which has been billed as the world's first robot capable of reading human emotions.

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Under the deal announced Friday, SoftBank will also buy five-year old Japanese robotics firm Schaft from Alphabet. It didn't say how much it was paying for either business.

The sale of Boston Dynamics marks a swift exit by Alphabet, which snapped up the company less than four years ago as part of a broader push into the field of robotics. That approach -- which saw Google invest in another seven robotics firms including Schaft in 2013 alone -- was led by Andy Rubin, the co-founder and former leader of the search giant's Android mobile unit.

Rubin left Google in 2014 to launch an incubator for tech startups.

Alphabet decided to sell Boston Dynamics after concluding that it wasn't likely to produce a marketable product in the next few years, Bloomberg reported. An Alphabet spokesman declined to comment on the reasons behind the sale.

"Robotics as a field has great potential, and we're happy to see Boston Dynamics and Schaft join the SoftBank team to continue contributing to the next generation of robotics," he said.

Boston Dynamics started in 1992 as a spinoff from the Massachusetts Institute of Technology, where it claims to have developed the first robots that ran and maneuvered like animals.

It now boasts a suite of advanced machines, including one that can run as fast as 32 kilometers an hour (20 mph). Another is designed to accompany Marines on duty while carrying loads of up to 500 kilos (about 1,100 pounds).

Related: Google shows off 'nightmare-inducing' robot

SoftBank last year set out its vision of branching into smart robotics, artificial intelligence and the so-called Internet of Things alongside its core telecoms business.

The announcement followed its $32 billion acquisition of U.K.-based chip designer ARM, which itself was seen as the Japanese firm's wager on growth in demand for internet connectivity in everyday devices.

Last month, SoftBank and Saudi Arabia's sovereign wealth fund launched the so-called Vision Fund, a $100 billion vehicle that will invest in areas including robotics and AI.