As of September 2021, here are the top 10 biggest tech initial public offerings (IPOs) globally this year:

1. Robinhood Markets Inc. – Raised $2.1 billion
2. UiPath Inc. – Raised $1.3 billion
3. Coinbase Global Inc. – Raised $1.3 billion
4. Palantir Technologies Inc. – Raised $1.1 billion
5. Bumble Inc. – Raised $2.2 billion
6. DigitalOcean Holdings Inc. – Raised $775 million
7. Coupang Inc. – Raised $4.6 billion
8. Deliveroo Holdings PLC – Raised $2.1 billion
9. Darktrace PLC – Raised $526 million
10. Squarespace Inc. – Raised $631 million

Please note that the rankings may vary based on the valuation at the time of going public and the amount raised during their IPOs.