The anonymous messaging app, which counts Renren as a backer, is reportedly valued at up to $400m, just seven months after a seed round raised at a $10m valuation.

Yik Yak, a US-based anonymous messaging app developer backed by investors including social network Renren, has raised $62m in series B funding, the Wall Street Journal reported on Monday.

The round, which was led by venture capital firm Sequoia Capital, values Yik Yak at between $300m and $400m, and brought its total funding to $73.5m. It was also set to include existing investors, though this has not been confirmed by Yik Yak.

Renren invested in Yik Yak’s $10m series A…