The only organisation related to the EU is the European Economic and Social Committee, which is[1]: a consultative body of the European Union (EU) established in 1958. It is an advisory assembly composed of "social partners", namely: employers (employers' organisations), employees (trade unions) and representatives of various other interests. ...ok? This does not strike me as a particularly important institution.

Some -- not all -- of the other cosigning entities are ridiculous. One of them (Normalzeit Leben) is literally the title of one person's blog where they talk about their struggles with DST.

[1] https://en.wikipedia.org/wiki/European_Economic_and_Social_C...