The clicking Morse code like sounds these creatures make are very complicated leading many scientists to believe it may represent a form or language. There is good evidence that there is actually different dialects of these clicks and that different clans of sperm whales may communicate a specific dialect among each other.
A team of scientists from Oregon State University, led by professor Bruce Mate, was able to tag several sperm whales from the same clan and track them very precisely using GPS. What they found was that the whales worked cooperatively to corral squid into a dense ball. Each whale took on a different role during this process and each one took turns at the hardest task. Some whales would do a deep dive to prevent the squid from diving to greater depths and others would enjoy eating in the middle of this dense mass of squid while still others would gather the squid up from the sides. This of course shows a great deal of orchestration and teamwork and it is thought that these whales are using their "language" to communicate during these complicated tasks.
I have personally listened to sound recording of sperm whales and it truly does seem like they are communicating with each other. Given that they associate in clans of thousands, it makes sense that they would develop a method of communication. They may in fact be one of the largest cultures on Earth.