Racehorse syndicator Dean Watt and his son Adam have failed in their appeals against fines totalling $20,000 for improper action.

Dean Watt, who is the head of Dynamic Syndications, and his son who works for the company, were found guilty of registering domain names and websites of leading trainer Chris Waller and rival syndication firm Triple Crown.

Visitors to the sites were directed to Dynamic Syndications, with at least one giving evidence he thought he was dealing with Waller.

Dean Watt was fined $10,000 and Adam Watt $2500 for the establishment of the domain name www.triplecrownsyndications.com and the establishment of the website page branded Triple Crown Syndications.

Dean Watt was also fined $5000 and Adam Watt $2500 for the establishment of the domain name www.chriswallerracing.com.au and the establishment of a website page branded Chris Waller Racing.

The Racing NSW Appeal panel upheld the convictions and penalties issued by stewards.