apple
License.txt doesn't define the licensor / copyright holder, nor the years
A common thing for Apache licensed software is to provide the "short" version in the readme. This can easily be copied for open source attribution pages.
The source code would potentially suggest this is that text:
Copyright (c) 2021 Apple Inc. and the Swift project authors
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
It's also possible that it should have a variation to mention the runtime exception, or link to the Swift.org mirrored license
Quick note: The snippet above used to have an incorrect copyright notice. This notices in this repository read Copyright (c) <years> Apple Inc. and the Swift project authors.
Ah, sure. I was extrapolating from swift-log, where I posted a similar issue.
Admittedly that looks like a pure Apache license, and is obviously an older project.