United fans wishing to display banners or, in some cases, flags inside the San Siro on Tuesday 16 February must first have them approved by AC Milan.
In line with Italian regulations, fans must supply a picture of the banner/flag and information about its size to the visiting club's Security Operative Group. After examining all submissions, the committee will notify each applicant of its decision to allow or prohibit the item from entering the stadium.
According to guidelines published on the AC Milan website, flags not in club colours may not be allowed into the San Siro, while two-stick flags or flags of excessive dimensions likely to obstruct other supporters’ views are definitely prohibited. AC Milan also prohibits drums, loudspeakers or “any other sound diffusion systems” into the San Siro.
Fans wishing to display banners must download and complete the relevant form on the AC Milan website before emailing it to firstname.lastname@example.org or faxing it to +39 0299786365 before 19:45 GMT on Tuesday 9 February.
More info: AC Milan