In an effort to prevent others from using variations on the "Pod" theme for naming portable music and video players, Apple filed an application for a trade mark for "POD" in 2004. In January the trade marks office rejected the application against the opposition of a music electronics vendor called "Line 6", which makes a line of products caled "POD" and has had a registered trade mark since 1999.
Aside from this decision showing that the trade mark registration and objection process takes an amount of time that is commercially unrealistic, it should stand as a warning to choose trade marks carefully. An ordinary word (or a simple derivation of one) is more likely to run into problems down the track than a distinctive word or phrase that does not appear in, or appear to be derived from, an ordinary English word. The "iPod" name, being one letter off an ordinary English word, is highly susceptible to problems of this nature.
This does not necessarily mean that Apple will not be able to take action against vendors using the "Pod" theme to capitalise on the Apple marketing of the "iPod" - in the right circumstances there may still be a claim for misleading conduct - however it may prove more difficult to enforce than a trade mark action.