If you, like Blawgletter, wondered when U.S. antitrust watchdogs would announce new standards for judging whether M&A deals have hurt or would injure competition, wonder no more. 

On April 20, the Antitrust Division of the Department of Justice and the Federal Trade Commission put out for public comment a new set of "Horizontal Merger Guidelines".  The 2010 HMGs will replace those from 1992 and 1997.

To our eye, the changes look mainly to furnish more ways to weigh anticompetitive effects.  The FTC summarizes the edits thus:

• The proposed Guidelines clarify that merger analysis does not use a single methodology, but is a fact-specific process through which the agencies use a variety of tools to analyze the evidence to determine whether a merger may substantially lessen competition.
• The proposed Guidelines introduce a new section on “Evidence of Adverse Competitive Effects.”  This section discusses several categories and sources of evidence that the agencies, in their experience, have found informative in predicting the likely competitive effects of mergers.
• The proposed Guidelines explain that market definition is not an end itself or a necessary starting point of merger analysis, but instead a tool that is useful to the extent it illuminates the merger’s likely competitive effects.
• The proposed Guidelines provide an updated explanation of the hypothetical monopolist test used to define relevant antitrust markets and how the agencies implement that test in practice.
• The concentration levels that are likely to warrant either further scrutiny or challenge from the agencies are updated in the proposed Guidelines. 
• The proposed Guidelines provide an expanded discussion of how the agencies evaluate unilateral competitive effects, including effects on innovation. 
• The proposed Guidelines provide an updated section on coordinated effects.  They clarify that coordinated effects, like unilateral effects, include conduct not otherwise condemned by the antitrust laws.
• The proposed Guidelines provide a simplified discussion of how the agencies evaluate whether entry into the relevant market is so easy that a merger is not likely to enhance market power. 
• The proposed Guidelines add new sections on powerful buyers, mergers between competing buyers, and partial acquisitions.  

For information on how to submit comments, look here.