Hull are looking into claims from a shocked supporter that he would be thrown out for TEXTING during the match.
Gary Lineker was among thousands to re-tweet the viral social media post from Daniel Mawer after his run-in with 'undercover security staff' at the KCOM Stadium.
The Football Supporters Association have offered assistance to the lifelong Tigers fan, who explained: "At half-time I was told by an 'undercover security guard', who came up to me holding a security badge followed by a steward that if I continued to text about the match I'd be ejected from the ground.
"He'd been watching me and asked what I'd been texting. It felt invasive and uncomfortable saying I'd been innocently texting opinions on the match to friends and family.
"He said if we continued we'd be ejected because there's trouble with people notifying betting companies at a match so they can cash out.
"I couldn't get my head around it. He assumed I was some sort of gambler's informant. I explained the club tweet details of the match much faster than I ever could, and that thousands of fans text and tweet throughout the match.
"This has never happened to me in 20 years of watching live football, but he said it was a new thing this season. I felt on edge, so I didn't text during the second-half."
Fellow fans reported the steward using binoculars to identify supporters on their phones, and Hull are investigating the incident which involved accredited staff from sports data provider Comsec's scouts enforcement programme.
A Hull spokesperson said: "We're liaising with a supporter who encountered a spot check from Comsec with regards to unauthorised data gathering at Saturday's match. Comsec are hired by Football Data Co to monitor the collection and distribution of official data.
"On request from the EFL the club accredited Comsec to do spot checks and we are working with them and the stadium management to understand how this check was handled."
The Football Supporters' Association said: "The way this has been managed doesn't seem especially professional."
Early goals from Jarrod Bowen and Jackson Irvine earned a first win for new Hull head coach Grant McCann, and midfielder Kevin Stewart said: "There's stiff competition for places in and that shows out on the pitch."
A debut effort from Lucas Joao failed to prevent back-to-to-back defeats to leave Reading in the Championship drop zone. The £7m arrival from Sheffield Wednesday said: "I'm happy to score but I'd rather have the victory than the goal."
