I see someone has posted this as a Google Maps review.
Couldn't have put it better myself
Two things. Firstly, these are not fines, they are invoices, a private company doesn't have the power to issue fines. Fancy solicitors not knowing the difference! Secondly, there is indeed an industry-wide grace period so everyone getting these invoices for stopping for a few minutes should simply refuse to pay. GXS are highly unlikely to try small claims court, and if they did they would lose. Free legal advice is available on several consumer advice sites on the web.