Legal Question in Civil Litigation in California

Generally, people have a right to do what they want within their property. Most courts have upheld that, unless it harms other people. Blocking your view, depending on the particular facts of your case, may or may not qualify as a private nuisance.

I would usually suggest to try if you could work it out with your neighbors. If you will hire an attorney, it would cost you, perhaps much more than what you value the view.