The Delaware Court of Chancery has rejected Enbridge Energy Partners’ bid to dismiss a shareholder suit targeting a $1 billion pipeline buyback deal, in a ruling that criticized the defendants for remaking arguments that had already been rejected by the state Supreme Court.

Vice Chancellor Joseph R. Slights III on Wednesday said EEP, a Delaware master limited partnership, had “returned to the well” in trying to dismiss the suit after the state high court revived derivative claims for breach of contract last March and sent the case back to Slights with “clear instructions” on how to proceed.