In your case you would need a single licence
LICENSING
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There are two types of licenses available
1.A single computer usage license. The user purchases one license to use the SOFTWARE PRODUCT on one computer.
2.A SITE usage license. The users purchases a single usage license, authorising the use of SOFTWARE PRODUCT, by the purchaser, the purchaser's employees or accredited agents, on an unlimited number of computers at the same physical site location. This site location would normally be defined as a single building, but could be considered to be a number of buildings within the same, general, geographical location, such as an industrial estate or small town.