| Clue | Source | Date |
|---|---|---|
| Grader's writing implement | Universal | 20 Jan 2024 |
| Test-grader's writing tool | USA Today | 25 Sep 2023 |
| Editor's tool | LA Times Daily | 11 Mar 2023 |
| Grading tool | Thomas Joseph | 26 Dec 2020 |
| Grader's tool | New York Times | 07 Aug 2019 |
| Grader's tool | ||
| Marker of mistakes | New York Times | 17 Jul 2015 |
| Marker of mistakes | ||
| Mistake marker |