In article .com,
FOM wrote:

I had a fence installed last year. It is three sides that enclose my
backyard. Yesterday, my next door neighbor installed a fence and used
my existing fence to complete enclosing his backyard. He did not ask me
if he could do this, he just had the installers attach his fence to
ours. Now, we are paying for one third of this guy's fence. Is this
legal? What should I do?


I'd do nothing. What do you want to happen?


Dimitri