First, let me say that I'm an engineer, not a lawyer, but I've been through the process. I've got a patent, and am quite familiar with many of the patents referenced in the Humminbird application.
Having said that, it looks to me to be typical of a refinement of many preceding ideas (including a Lowrance patent that talks about side looking sonar) and the lawsuit will likely come down to who wants to spend the most money on lawyers...
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