Good choice, but why was it a secret?
I doubt it is, but this is still odd behavior.
At the Adventures of Tintin panel at the 2011 San Diego Comic Con, Steven Spielberg gave an update on the future of the Jurassic Park franchise. Spielberg revealed that they have come up with a story for a fourth film, and they currently have a writer working on a treatment. He enthusiastically added that “and hopefully we’ll make it in the next two or three years”.
Further proof that nothing is sacred.