I know that this is not allowed but I should imagine that since COVID sprung the concept of the part-office, part homeworking lifestyle, that sharing Oyster weekly/monthlies with partners/friends is becoming more and more prevalent among the citizens of London. It would not surprise me if the number of people who do this is well into the thousands. This makes me wonder just how much money TfL is losing out on every day by opting not to insist on a photocard for season tickets. Considering how long Oyster has been around I'd have thought it was an eye-watering figure, but if so it is somewhat surprising that they have never done anything about - a quick Google of these forums as well as the general internet does not give any hits on stories about people prosecuted or even fined for sharing. So perhaps it's not really a problem or they've decided it's impossible to police so just write it off. Thoughts?