In Swedish it's Brasklapp, which sort of translates to Brask note.
First of all, I looked it up on the Swedish version of Wikipedia. Not surprising, there it was (http://sv.wikipedia.org/wiki/Brasklapp). Then I thought "my readers are probably English speaking, I should try the English version of Wikipedia as well". The word didn't have a post of it's own. No wonder, since it's a Swedish expression. But the guy who the word refers to, Hans Brask, is mentioned in the English version of Wikipedia (http://en.wikipedia.org/wiki/Hans_Brask).
The story goes that Hans Brask, bishop at the time, was a member of the council of the realm. One of the things that was decided upon was the removal of another bishop, Gustav Trolle. Brask was opposed to this decision, but eventually put his mark and wrote his name on the official document.
Three years later, Kristian II took over Sweden. What does the new boss do when he gets the power? That's right, get rid of the other guy and all his minions. Among these were many of the Swedish nobility. After the trials towards these 95 men they were all taken to Stockholm's square and executed. This is what is known as Stockholm bloodbath (http://en.wikipedia.org/wiki/Stockholm_Bloodbath). But "only" 94 men were executed, what happened to the 95th?
This is the part where the main character comes in, Hans Brask. During the trials, he told that his seal held a written note. This was examined, and was found to be true. In fact, under the seal was a note with the words "Härtill är jag nödd och tvungen! [To this I am forced and compelled]. This meant that he had taken reservations against the decision and therefore was a "good guy", since he wasn't actually opposed to Gustaf Trolle.
Thus was born the legend. Is it true? Who knows. It's difficult to prove, almost 500 years later. Try proving something that happened yesterday, and then imagine that all the witnesses are dead and didn't leave a note. Either way, his name and deed will forever live on as the phrase Brasklapp. It means that the signer reserves his opinion against the decision, but feels compelled to sign it anyway. Sometimes it's hidden, but more often than not, it's in clear sight.
I remember thinking, when I first heard about this story, that he probably left notes on a number of places, and would've reveled them if the other guy had won. No proof exist of this of course, it's just one of those things you think when you eight or nine years old and devious.