High-profile bookmaker Tom Waterhouse has sold down his shareholding in BetMakers, the ASX-listed wagering technology group that is a major partner in the News Corp-backed online gaming operator Betr.

Mr Waterhouse sold $4.6 million of his shares in BetMakers this month, according to disclosures made on Friday, and is no longer a substantial shareholder in the company. BetMakers shares have fallen more than a third since the start of the year. They last traded at 18¢.