Once an author assigns copyright in a work to another person or company, the author may no longer reproduce or authorize reproductions of that work; to do so is infringement of copyright. The Copyright Act also states that it is infringement of copyright for anyone other than the owner to reproduce "a substantial part" of the work in any material form. Substantial part is not defined in the Copyright Act, and is examined from both a quantitative and qualitative perspective.

From a quantitative examination, a Court will examine the actual amount of material copied. If only minor modifications are made from the original, it is likely that the "new" work will be found to infringe copyright.

It does not necessarily follow that reproduction of only a small percentage of a work will not be found to infringe copyright. From a qualitative standpoint, if the small part of a work which is taken is the central or key portion, it may also be found to infringe.

Copyright subsists in "every original literary, dramatic, musical and artistic work." Copyright does not subsist in bare ideas or facts, but does exist in a form of expression of those ideas or facts. For example, an idea for a new drug, or the fact that it was released is not the subject of copyright. However, a newspaper article on the drug or its release will be the subject of copyright.

This response is provided for information only, and should not be taken as legal advice. Anyone who has specific concerns regarding copyright is advised to obtain the opinion of counsel.