On Wednesday, a report suggested that West Ham were ready to rival both Real Madrid and Barcelona in the race to sign the 21-year-old, who has impressed in La Liga this season.
Moyes and assistant Stuart Pearce have previously been seen at a Real Betis match, but the Scot has claimed that the pair were not specifically in attendance to view Ruiz.
At a press conference, the 54-year-old told reporters: "No, that's not right."
When quizzed on scouting in general, Moyes added: "Do you think that's strange? Managers go and watch games, whether it is different countries or whatever, we want to be as up to date as we can. Yeah, we were at games."
Moyes has confirmed that Inter Milan midfielder Joao Mario is on the brink of moving to the London Stadium on loan for the rest of the season.