The moral obloquy arises because the 1987 crash taught the options market that unrestrained, unhedged or inadequately hedged put sales threatened not just the seller but the market as a whole. A collective response to the danger came in two phases. First, options clearing firms themselves changed their riskmanagement practices in response to 1987, for example by starting to check the consequences for each trader who cleared via them of a repetition of the crash (Hinkes interview 2).

Donald MacKenzie, An Engine, Not a Camera, loc. 931