Spiber Inc. announced that it that it will issue 5,422,222 common shares at a price of ¥4,500 per share for gross proceeds of ¥24,399,998,000 in a round of funding led by new investor, The Carlyle Group Inc. on September 8, 2021. The transaction will include participation from new investors Fidelity Management & Research Company LLC, Baillie Gifford & Co., existing investors Cool Japan Fund, Inc., Tokyo Century Corporation, The Yamagata Bank, Ltd., Satake Chemical Equipment Mfg., Ltd. and other investors. The Carlyle Group Inc. has done minority investment for ¥10,000,000,000.

The transaction was made through a combination of the allotment of new shares and a capital infusion. The round is raised at a post-money valuation of around ¥135,000,000,000. The Carlyle Group Inc. and Cool Japan Fund, Inc. will each send one director to serve on the company's board of directors.

The number of outstanding shares of the company (excluding treasury stock) after this capital increase will be 29,565,875 shares.