The five federal e-file limit is an IRS limit. If you have more than five federal returns to file, you can file them by mail. And, no, purchasing additional CD/downloads is not a way to get around the IRS limit. If you have so many tax returns to file that you are asking about putting the software on five computers to file five returns on each one, you should be looking into purchasing the professional tax software, like LaCerte or ProSeries.
https://accountants.intuit.com/?s_cid=TT.com_MoreProds-Footer_ProTaxSoftware
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