Originally Posted by
PhilipK
My understanding is that there is no requirement in UK law for documentation to be sent Signed For. The courts regard the UK postal service as sufficiently reliable - hence documentation like NIPs, V5s, etc are sent by normal post.
If it comes to a "he said, she said" discussion, my guess is that the courts would accept the word of a reputable[*] organisation that they had posted it. They might be able to back that up by showing that other documentation they had sent has been received by the intended recipients.
[*] For some value of "reputable".
Pepipoo, as mentioned above, is your best bet. There's also a sub-forum on Money Saving Expert dedicated to assisting people with parking disputes. But please, please, please don't refer to it as a "fine" - a private company cannot issue a fine.