The deal is unusually personalised for a chief executive of a major company, with Schultz himself sitting on the board of Square.

Howard Schultz, executive chairman, made a big splash in August, taking his coffee retailer into corporate venturing by  backing mobile payments provider Square.

The deal is unusually personalised for a chief executive of a major company, with Schultz himself sitting on the board of Square.

It seems Square’s founder Jack Dorsey is enjoying working with Schultz, regularly using the other company he founded, Twitter, to comment on the latest wisdom Schultz has bestowed on him.

The move marks a slight change in Schultz’s relationship with start-ups. He has long been an investor through venture firm Maveron. Last year he took a seat on the board of hotly feted daily deals start-up Groupon.

As Groupon faltered on the public markets, Schultz stepped down from the board this year. Whether Schultz’s foray into corporate venturing with Square was an opportunistic, strategic move or a sign of more things to come is so far unresolved.