(I'm not an orbits expert, but I do work for Planet Labs, and we're sending up piles of cubesats.) The actors puting objects up in orbit are trying hard to be

(I'm not an orbits expert, but I do work for Planet Labs, and we're sending up piles of cubesats.) The actors puting objects up in orbit are trying hard to be good neighbours these days. Our cubesat missions are designed such that should we completely lose control over a satellite the orbit will naturally degrade and re-enter the atmosphere on a ~10 year time scale. Our hardware deployed from the ISS is gone in less than two years. It's my understanding that it is required of us (and most groups in general) to plan our missions such that they will naturally de-orbit within 25 years.