South_agency/Getty ImagesPoly Network offered its cyber-hacker a $500,000 bug bounty days after it had lost $610 million. Reuters first reported.DeFi said that it will give the money to "help us improve Poly Network’s security."The hacker has already returned almost all of the assets except for the $33 million worth of frozen tether coins.Subscribe to our daily newsletter 10 Things Before The Opening Bell.Poly Network offered its cyber-hacker $500,000 in a "bug bounty" just days after DeFi lost $610 million. This is considered to be one of the largest cryptocurrency heists ever.Poly Network stated that the amount is to "help us improve Poly Network’s security," Reuters first reported. It cited a statement it had reviewed.Reuters reported that the platform said it also hoped the hacker it calls "Mr. White Hat" would contribute to the development of the blockchain sector after accepting the $500,000 reward.According to Reuters, it is not clear in what form the bounty of $500,000 will be paid and if the hacker will accept it."After communicating with Mr. White Hat we have also come up to a greater understanding regarding the way the situation unfolded, as well as Mr. White Hat’s original intent," Poly Network stated in a statement viewed on Reuters.White Hat is the industry term for hacking for ethical reasons.According to a Poly Network statement, August 12, the hacker had returned almost all of the assets except for the $33 million worth of frozen tether coins.Poly Network made the hack public on August 10, and asked for the funds back. On August 11, the hacker began siphoning off the funds.According to a Q&A session embedded in ethereum transactions sent out from the account that held the stolen assets, the hacker claimed that he or she took the funds "for fun ;)"Tom Robinson, cofounder and chief executive officer of Elliptic (a blockchain analytics company and compliance firm), took the screenshots.The hacker stated that the Poly network was a good system. It's one the most difficult attacks a hacker could enjoy.According to hackers, he or she took the money after finding a bug and "to keep it secure."This latest heist highlights the risks associated with decentralized finance platforms that allow transactions without traditional protections from exchanges or banks.Continue reading: Tether's cofounder and 2 crypto experts discuss the myths Congress holds about the industry. They also explain how they will reconcile the two sides in the future.