Capoue has been a key player for Watford since their return to the Premier League, making 79 top flight appearances for the club following his move from Tottenham in 2015.
Last season, the Frenchman was fantastic for the side, scoring seven times to finish as the club's second highest goalscorer in the league. This season however, it has been a lot more of a struggle for the holding midfielder.
He has started just four times, making a further five appearances from the bench for Marco Silva's men. And now the Mail reports that Watford may be prepared to sell Capoue this month, and he may be ready to leave Vicarage Road.
The Mail adds that the Irons are fans of his, but Watford's asking price is set to be around the £12 million mark, and there is no indication whether their Premier League rivals would be willing to meet that price.
While Capoue was often exceptional last season, it may not be too great a surprise if the Hammers fans need to be convinced about whether he would be a good target to go after as they look to get themselves out of trouble in the top flight.
West Ham's transfer record in recent years has been mixed, and going after a player who is at an age where he would presumably not have too long left at his best, and is not actually in the best form right now may seem like a questionable idea at this stage.