Usually, investment bankers will informally "shop" the assets around, which can be thought of as more of a negotiation than a formal auction.
...use negotiation when flexibility (like change orders) is important, as is likely for large complex projects; and if you negotiate, use a reputable firm because you are subject to hold up when unforeseen contingencies arise. Contracting with a reputable firm can reduce the risk of hold-up.
In this case, I suspect that what the papers are reporting as an auction, is better described as a negotiation. BofA/Merrill has a reputation to protect.