LinkedIn likes to portray itself as the professional social network, but it seems it is perfectly happy to treat its professional users as fodder for advertisers without asking -- as exploitative as the consumer-grade arseholes at Facebook. Word has been slowly spreading among LinkedIn users this week that they've all been signed up to the company's "social advertising" program -- without being asked. It's exactly the kind of swifty that Facebook regularly pulls and that triggered a backlash against that social network last year. "Social advertising", you ask? "When LinkedIn members recommend people and services, follow companies, or take other actions, their name/photo may show up in related ads shown to you," reads LinkedIn's explanation. "Conversely, when you take these actions on LinkedIn, your name/photo may show up in related ads shown to LinkedIn members." Advertising is likely to be more effective if it's accompanied by the face of someone you know, sure. Welcome to psychology. If you've already indicated in some way that you have an interest in a company or its products and services -- "take other actions", whatever they are, thanks for the programmatic specificity there -- then LinkedIn takes that as a sign that you endorse them and will happily include your name and image in that company's adverts. There's two problems with this. First, if I follow a company on LinkedIn it's because I'm interested in it in some way, not because I want to become its shill. I might just be looking for job. Traditionally, anyone lending their name and image to endorse an advertiser would be paid for it, and paid quite well. A major brand might pay a couple thousand dollars for an unknown model to appear in a one-off newspaper advertisement, for example. At the very least, you ask first. Second, the entire concept of turning on this setting and relying on people to opt out if they don't like it is dodgy practice, as any ethical operator will tell you. It might even be illegal, at least in the Netherlands. "The Dutch Data Protection Authority (CBP) says LinkedIn should have asked its users to give their explicit consent to the use of their portraits as illustration material in its advertising," reports Radio Netherlands. "Lawyer Milica Antic told Webwereld magazine that LinkedIn has put its foot wrong twice over: by offering an opt-out instead of an opt-in, and by failing to properly inform its users about the change in the terms of use," they report. LinkedIn reckons it ran a banner advertisement announcing the change, but Antic reckons neither she nor anyone she spoke to ever saw it. Neither did I. How could LinkedIn be so stupid? If you're a LinkedIn user and want to opt out of all this, go to where your name is displayed on the top right of your LinkedIn screen and click on "Settings". Click on "Account" at the bottom left of screen, then "Manage Social Advertising". Disclosure: Stilgherrian receives a free LinkedIn Pro account as part of its media outreach program.