I worked in Finland in 2001-2002 in what we would call now startup and even lead managers or scientists in company were not in the office in July-August. They simply worked more during winter and spent as much of Finnish summer outside as possible. But as article mentions, it was usual to take long vacations even in government jobs - if you needed visa for your relative, you'd better have it before June, or you would get it in September, since clerks were out of office :).