DarrenA, what version of Sage CRM are you using?
Try the following code in the person last name Create Script field.
Caption = CRM.GetTrans("colnames","pers_lastname")+":";
var strLinkedInProfile = Values("pers_linkedinpublicprofile");
if ((Values("act")==220 || Values("act")==222 || Values("act")==520) && strLinkedInProfile)
var strProfileBadge = "";
Caption += strProfileBadge;
You need to be careful as when saved the end will be changed to which then when you try to save will just return 3 fields on the CRM screen. You will need to make sure each time you amend the screen the code is changed back.
You could however place it into a js file in the custom folder and call it from there instead.