One highlight of Walter Treser's 1987 convertible was a space-saving single-piece retractable roof. After Treser's firm declared bankruptcy in 1988, the patents for the roof system went to a Berlin bank that later sold them to Mercedes-Benz.
'I won't say that I have invented this roof for the SLK,' said Treser. 'But it proves that I developed an old [1935 Peugeot] idea at the right time for modern application.
'It does not matter if you have the first idea, but you have to implement it in such a way that the advantages are available when the customer needs them,' he said. 'Therefore, I do not care too much about patents.'