After obtaining $300 million in its Series C fundraising round on Tuesday, NFT marketplace OpenSea has surpassed a valuation of $13 billion. The round was headed by Paradigm and Courtue, with participation from new and current investors, according to a press release published late Tuesday. The latest fundraising is a significant increase from the company's $100 million Series B funding in July, which resulted in a $1.5 billion valuation.