The amount marks the first close of a larger round for the Mynavi-backed online advertising platform, though the target size has not yet been revealed.

US-based advertising platform C1X, backed by corporates including media company Mynavi, has secured $8.5m in a first close of its series B round, according to TechCrunch.

The round was led by venture capital firm Venture Labo Investment and included unnamed existing investors. C1X has not disclosed its target for the round.

C1X operates a platform that offers direct and real-time bidding tools that faciliate advertising campaigns on thousands of websites. The technology makes it easier for publishers to target their…