I want to know the answer to the following question:
Which competitor sued Apple over rights to part of the software user interface?
All the background I'm provided with is that "Also in August 2005, Creative Technology, one of Apple's main rivals in the MP3 player market, announced that it held a patent on part of the music selection interface used by the iPod line, which Creative Technology dubbed the "Zen Patent", granted on August 9, 2005.". Is that enough to answer the question?
Answer: yes