I'm looking at a repository with the BSD-3 license in its LICENSE file, but in which the source files say:
Copyright (c) Big Corp Inc. All rights reserved.
When I redistribute / modify, and include the copyright notice and BSD-3 terms, Do I need to say that "All rights reserved" for Big Corp Inc. ? Even though that is literally not true and they don't reserve all rights? Or is it enough if I say
Copyright (c) Big Corp Inc. Modifications Copyright (c) 2020 Joe User. [BSD-3 terms here]