Costanoa Ventures has led a $10.5m round for the landline-based smart messaging platform that also featured Alphabet's AI-focused Gradient Ventures fund.

Gradient Ventures, the artificial intelligence-focused fund owned by internet and technology conglomerate Alphabet, has invested in US-based business messaging service NumberAI as part of its $10.5m series A round, according to VentureBeat.

The round was led by Costanoa Ventures and included another venture capital firm, DFJ, the latter having previously supplied $1.6m in seed funding for the company, TechCrunch reported in October 2017.

Founded in 2016, NumberAI has developed an artificial intelligence (AI)-based platform called Numa that enables businesses to…