This appears to be a bit of a sensationalist story. While its possible they seized the Silk Road escrow funds, since I believe I read in court docs they had physical control of the server. I don't believe they have control of Dread Pirate's personal wallet, only a copy of the wallet file. Unless Ulbricht, if he is in fact DPR voluntarily reveals his private key, which would tie him to the allegations against him, or the NSA finishes their quantum computer and starts going to town on this file. DPR retains control over the supposed 600k BTC stash as of now.
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