The most common and most likely answer to this crossword clue is the 6 letter word BROOKS
I've seen this crossword clue in Financial Times
B
R
O
O
K
S
More clues leading to the result BROOKS
Buddy explains!

The straight part
We know that "permits" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case permits = brooks.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 BROOKS mean?
BROOKS verb- To use; enjoy; have the full employment of.
- To earn; deserve.
- To bear; endure; support; put up with; tolerate (usually used in the negative, with an abstract noun as object).
- A body of running water smaller than a river; a small stream.
- A water meadow.
- (in the plural) Low, marshy ground.