The negation over funds was not about "fair market price" - the whitehat was testing them. He had returned 85%, showing honesty but seriousness, and Blockstream offers only $1.5m.
This revelation of greed instead of gratitude is going to be leveraged by the whitehat to justify his theft in his own mind, viewing it as justified against an evil corp and a statement against the poor treatment of vulnerability researchers.
quotingHacker responds in plaintext
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"Your dereliction of duty is obvious that you allocated only $1.5M (maybe even 0) to secure $5B assets. This is a flagrant neglect of security and a sign of complete mismanagement. You SHALL pay 10% using your own money as bug bounty or you will cause all your holders a 15% loss for your irresponsibility and stinginess. Even companies that participate in bug bounty programs cannot guarantee complete security, let alone one like yours that remains delusional, greedy, and arrogant to this very day. Anyway we are going to publish the privatekey to decrypt our conversations afterwards. "
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