Dominion Resources, the Virginia-based power producer, on Friday sent letters to both Duke Energy and Progress Energy with "soft" offers to buy each at a 10- to 15-percent premium to their stock price after learning of their plans to merge, according to people familiar with the situation.
Dominion had been engaged with Duke in occasional takeover talks and when word of the potential Progress deal leaked out late last week, Dominion tried to prevent the union by making offers for the companies, despite knowing the last-gasp effort was not likely to succeed.
In its letters, Dominion said it would not make any offer public, indicating an unwillingness to mount a public campaign to try and break apart Monday's deal.
People close to Duke told CNBC that the letter was not deemed actionable because it lacked specifics on key terms and who would head the company, all of which had already been hammered out by Duke and its board as it put the finishing touches on the deal to merge with Progress.
The deal between Progress and Duke was announced Monday morning, and given how difficult it is to undertake hostile deals in the utility industry and its unwillingness to make its offers public, it is not expected that Dominion will continue to try to break it up.
Dominion Resources had no comment.
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