COPYRIGHT - eliminate redundancy

In the COPYRIGHT field I often find strings like

2023 Blues Route / Delta 2023 Blues Route / Delta

The texts contain a different even number of words.
I would like to eliminate the obvious redundancy in the text.
After correction, I would like to get the following:

> 2023 Blues Route / Delta

How to do this?

See this thread which deals with the field GENRE.
I am sure that you can adapt it to work with COPYRIGHT:

Thank you for this hint.
As I don't understand :thinking: the expression

$regexp($reverse($regexp($regexp($reverse($regexp($regexp(%Genre%,'^(\s+;*|\s*;+)+|(\s+;*|\s*;+)+$|((?<=;)\s+)|(\s+(?=;))',),'^|,';')),'(;[^;]+)(?=(\1|;.*?\1))',),'^;+|;+,)),'(?<=;)',' ')

in detail, I am not shure how to deal with this.
--.--
Another idea is to find the beginning of the redundant second part of the string and split COPYRIGHT in 2 values and delete the second one. But stil have to build an expression that scans the string ....

I would have thought that you replace every reference to %genre% with %copyright% and then try it in Convert>Tag-Tag for COPYRIGHT.

There is no logical link between GENRE and COPYRIGHT.
In COPYRIGHT you will often find
a) the holder of the copyright
b) the representative of the trademark
I use COPYRIGHT and use it synonymously with the value of PUBLISHER.
My goal here is to reduce or merge to one value.

The regular expression deals with the contents of GENRE as you can see in

To make that work with COPYRIGHT or if you like PUBLISHER, you have to replace %genre% with the fieldname that you want to treat, so it should become
...$regexp($regexp(%copyright%,'^(\s+;...
or
...$regexp($regexp(%publisher%,'^(\s+;...
or whatever field you want to treat.

Ok, I misunderstood your hint.
I will try this and give feedback. :wink: