Right now, the use of the old-fashioned signature in a digital age begins to loose its viability. It's too easy to duplicate or digitally copy a signature. However, in our society there is a huge need to provide documents with a signature. Suppose there is an unchangeable database (blockchain), which contains documents that contain unambiguous and verifiable signatures (gpg) ?
This combination of software does not exist at this time, but it is indispensable in a modern digital infrastructure. For example, think of being able to quickly and verifiable sign documents such as search orders and court judgments by a judicial authority. This seems a hole in the market for a commercial company, but do we as a society want that? A society that relies on product X of company Y? Where municipalities, courts and countries can all buy from any vendor? Do we not prefer a uniform standard that is free of charge and where an ecosystem of companies has arisen to provide services? There is only one Internet in the world, and that is open to everyone. There is only one Linux in the world, but it’s used widely in Android, DVD players, TVs, and even cars. What happens if companies that deal with important IT infrastructure issues (think of text documents or the Dutch data model for it’s citizen database) and become de facto standards is assumed to be well known.

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