The $50 million funding round, completed in August, also included Fifth Wall Climate Technology Fund and Jony Ive, Apple's former chief design officer, and other existing investors including Deutsche Boerse.
The appetite for reliable data is growing as companies are increasingly graded on their sustainability credentials and regulators in Europe and elsewhere begin to demand clarity in formal disclosures about the impact of business activities on the environment and society.
So far, more than $30 trillion has been invested in major markets using some form of sustainability strategy, the Global Sustainable Investment Alliance has found.
Softbank's Vision Fund 2 currently has around $40 billion in committed capital from the company and its founder Chief Executive Masayoshi Son.
Vision Fund 2 and its predecessor Vision Fund 1 have a reputation for backing companies perceived as leaders in their field by providing large cheques that can enable them to scale quickly.
Clarity AI uses big data and machine learning to help clients customise analysis on 30,000 companies, 135,000 funds and 375 countries and local governments.
"Our technology shows our clients how their investments and other organisations are impacting the world," Clarity AI founder and Chief Executive Rebeca Minguela said.
"The social and environmental challenges the world faces and the corresponding economic opportunities unlocked have put impact assessment at the forefront of the minds of investors and organisations."
The latest fund raise comes after BlackRock, the world's biggest asset manager, in January took a minority stake in Clarity AI, with a plan to integrate it into its portfolio management system, Aladdin.
Clarity AI has also struck deals with other fund platforms including Allfunds, the world's largest global fund distribution network.
Clarity AI said the money raised in the Softbank-led funding round would be used to develop its technology, hire staff and expand into new countries and market segments.
"The sustainable investment market is already more than one third of total global assets and growing rapidly," Jimi Macdonald, investor for SoftBank Investment Advisers, said.
"Empowering investors to make informed decisions about social and environmental impact is a real differentiator."
(Reporting by Simon Jessop; additional reporting by Sam Nussey in Tokyo; editing by Barbara Lewis)
By Simon Jessop