The amount of money raised by cryptocurrency and blockchain start-ups via so-called initial coin offerings (ICOs) has surpassed early stage venture capital (VC) funding for internet companies for the past two months.

ICOs are a way for start-ups to raise money from users, similar to crowdfunding, by allowing them to buy a stake. In return, the user will receive a token or digital currency, which are equivalent to shares in the firm. ICOs are popular among cryptocurrency and blockchain start-ups and have exploded in the past few months.

The total amount of money raised via ICOs in April was just under $100 million, but by May this had more than doubled to almost $250 million, according to Coinschedule, a website that tracks such data. In June, ICO funding had hit over $550 million and it was the first month ever that it surpassed angel and seed VC funding. This was noted by Goldman Sachs in a note released Tuesday.

Angel and early VC funding in June was just under $300 million, Goldman noted, according to CB Insights data. In July, ICOs were just over $300 million, while angel and early VC funding was just over $200 million.