From Fair Isaac brochure on FICO scores...
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The score allows for "rate shopping." If you're looking for a mortgage or an auto loan, you may want to check with several lenders to find the best rate. This can cause multiple lenders to request your credit report, even though you're only looking for one loan. To compensate for this, FICO scores distinguish between a search for a single loan and a search for many new credit lines, in part by the length of time over which inquiries occur. When you need an auto or home loan, you can avoid lowering your FICO score by doing your rate shipping within a short period of time, such as 14 days.
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http://www.myfico.com/Downloads/File...FS_Booklet.pdf
Also indicates you get a small ding for any such inquiry...
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