As an AI language model, I can provide information about some of the most significant data breaches that occurred worldwide in 2021. However, it’s important to note that data breaches can be dynamic, and new breaches may occur over time. Here are ten notable data breaches from this year:

1. LinkedIn: In April 2021, information of over 500 million LinkedIn users, including email addresses, phone numbers, and other personal details, was exposed on a hacker forum.

2. Facebook: In April 2021, data of around 533 million Facebook users from over 100 countries was leaked online, including phone numbers, full names, locations, birthdates, and biographical details.

3. T-Mobile: In August 2021, T-Mobile suffered a massive data breach affecting approximately 54 million customers. Personal data such as names, dates of birth, social security numbers, and driver’s license information were compromised.

4. Ubiquiti: In January 2021, network device manufacturer Ubiquiti discovered a data breach affecting its customer accounts. While the extent of the breach is unclear, there is potential risk to customer information.

5. EA (Electronic Arts): In June 2021, hackers gained unauthorized access to EA’s network and stole important source code and tools used for game development. The breach exposed sensitive data of approximately 780 GB in size.

6. Gunnebo: In August 2021, a Swedish security firm called Gunnebo suffered a major data breach. Hackers leaked over 38,000 files containing sensitive data, including access control details and client information.

7. JBS Foods: In June 2021, JBS, one of the world’s largest meat processors, was hit by a cyberattack that affected its operations across the United States, Australia, and Canada. While the breach didn’t directly expose customer data, it disrupted the meat supply chain.

8. Carnival Corporation: In March 2021, the world’s largest cruise company, Carnival Corporation, announced a data breach that exposed personal information of guests and employees. The breach affected multiple cruise line brands under Carnival Corporation.

9. CD Projekt Red: In February 2021, the game developer responsible for popular titles like Cyberpunk 2077 and The Witcher 3 reported a data breach. The attacker accessed internal systems and stole source code, game files, and employee information.

10. SolarWinds: While the SolarWinds breach was initially discovered in late 2020, its impacts continued into 2021. Multiple government agencies and organizations were compromised through SolarWinds’ software, potentially exposing sensitive information.

Please note that the severity of breaches and the information disclosed can vary. This list highlights some notable breaches but doesn’t encompass all incidents that occurred this year.