Patent search firms are business that perform database and library
research for patent-related cases.  There are many different types of
searches typically offered by search firms.  An overview can be
found at http://www.gilmanresearch.com/pages/944486/index.htm

I would like to know:

(a) The total number of patent search firms.  I would prefer this
information to be from a reputable source.  If someone merely counts
the number of links from Yahoo or Google Directory, I'm afraid that it
will underrepresent the true number.  The number of firms in the US
would be fine.

(b) Some indication of the yearly revenue for some of the large US search firms.  

Thank you,
Chess

Geting a list of the largest US law firms specializing in patent law
and their revenues is pretty easy, as is obtaining lists of patent
brokers.

I've found one reputable and often-recommended list of patent search
firms, but it may be missing other patent search firms.  There's no
SIC /NAICS code specifically for patent search firms such as the one
you named. And Gilman Research falls under the SIC code listing of
"research service" - it's not listed under a SIC/NAICS code related to
patents.

Thank you very much for your help.  I would like to pay you for the
information that you already have, specifically:

(1) The list of largest US patent law firms and revenues.
(2) The often recommended list of patent search firms
(3) You 'modus operandi' for determining the SIC code for a particular
company, i.e. Gilman Research.

However, I don't want to mark this question "answered", in case
someone can actually answer it.  Should I create a new 'dummy'
question?

Zach

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