It is good to have a copyright notice next to the license notice in your files. That give the users of your code some indication who the rights holders are.
A properly formatted copyright notice has the format
Copyright <year> <rights holder>
where the year is a list or range of years in which (copyright-significant) changes to the file were published and
rights holder is the name of the person or legal entity that owns the copyrights on those changes.
If there are multiple contributors at different times, then you can have a separate copyright notice for each of them. If there are really many contributors, people tend to combine the list or rights holders in a smaller number of copyright notices.
The "All rights reserved" indication you have I would recommend to drop, as it is contradictory to the license indication that follows and can cause confusion.