The most common and most likely answer to this crossword clue is the 8 letter word ARTICLED
I've seen this crossword clue in The Times
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More clues leading to the result ARTICLED
Buddy explains!
The straight part
We know that "bound by written contract" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bound by written contract = articled.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ARTICLED mean?
ARTICLED verb- To bind by articles of apprenticeship.
- To accuse or charge by an exhibition of articles or accusations.
- To formulate in articles; to set forth in distinct particulars.
- Bound under the articles of an apprenticeship