The most common and most likely answer to this crossword clue is the 8 letter word SPURIOUS
I've seen this crossword clue in The Daily Telegraph
S
P
U
R
I
O
U
S
More clues leading to the result SPURIOUS
- In team I am indebted - debatable
- Forged note of indebtedness accepted by football club
- Deceitful financial documents after initial incentive
- Dodgy inspection of unmentionables starts in one side of London
- Mock London club riven by sign of debt
- False encouragement given on debts
- Debt taken on by football club, not Real
- Bogus debtor’s note held by London players
- Contrived incentive facing debts
- Bogus record of what’s outstanding in London team
Buddy explains!

The straight part
We know that "False" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case false = spurious.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 SPURIOUS mean?
SPURIOUS adjective- False, not authentic, not genuine.
- Extraneous; stray; not relevant or wanted.
- Bastardly, illegitimate