Correct. There is no "abandonment" concept in current copyright law. The exclusive rights of the copyright owner last for the entire term of the copyright - even if he/she never showed the work to another person and hid it in a drawer from the date the work was created. The only ways to "give up" your exclusive rights in a copyright are either to transfer them to somebody else or to make a clear definitive affirmative statement that you are intentionally committing the work to the public domain.
Contrast trademarks (such as the term "Star Trek") - trademark rights can be deemed abandoned if the owner goes for some prolonged period of time without using the trademark on any goods or services. But even here, there is no "default time". Rather, even if the period of non-use has continued for years, the law will only find abandonment if all of the other attendant circumstances (in addition to the lapse of time) indicate that the owner intended to cease and not resume using the trademark at some point in the future (for example, the company dissolves, all the factories closed, etc.) For clarity, even if there had been no ST movies or TV shows for years, the continuation of use of the term "Star Trek" on merchandise would be enough to keep the mark from being deemed wholly abandoned.
M
