This is a virtual operation that is created while reviving a bitasset from collateral bids.
[ 39,{ "fee": { "amount": 0, "asset_id": "1.3.0" }, "bidder": "1.2.0", "debt": { "amount": 0, "asset_id": "1.3.0" }, "collateral": { "amount": 0, "asset_id": "1.3.0" }, "extensions": [] } ]