The round was led by Verizon Ventures, the venture arm of telecommunications conglomerate Verizon, and Bullpen Capital, a post-seed stage investment firm.
Venture arms for Intel and US airline JetBlue also took part in the round, along with CME Ventures, Lab IX, Backstage Capital, Tappan Hill Ventures and existing investors Digital Currency Group, Resonant Venture Partners and Samsung NEXT.
The startup had raised more than $9m as of February, SEC documents showed at the time, and the round comes less than two years after Filament raised $5m in a Series A round in August 2015. Verizon was among the companies to take part in that round, signifying its first foray into the blockchain space.
In statements, those backing the IoT-focused startup – particularly JetBlue, the sixth-largest airline in the US – suggested that their involvement could impact the way their respective companies do business.
Bonny Simi, president for JetBlue Technology Ventures, said:
As part of the deal, Intel Capital's Patrick Walsh will gain a seat on Filament's board of directors. In a statement, Walsh echoed Simi in remarking that his firm's work with Filament would tie into the blockchain efforts being pursued at Intel.
"Intel is creating transformative technologies to enable large-scale Industrial IoT deployments, and our investment in Filament will help support that vision," he said.
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