biopic - How can a studio make a biographic film like The Social Network?

Do the film makers take permission of all the real people (that were portrayed in the film) before making the film?

If not, is it okay / legal for anyone to make such a film - considering that it portrays (down to using the real names of) people who are alive during the screening of the movie - especially if many of the parts of the film are "apparently" inaccurate?

I tried searching in relation to The Social Network and could not get any definite answer. What I got was this following quote from IMDB:

Facebook CEO Mark Zuckerberg was not involved with this film
adaptation of author Ben Mezrich's biographical novel 'The Accidental
Billionaires', neither did he meet Jesse Eisenberg prior to, or
during, the movie shoot.

Answer

No one owns the story of their own life. It is absolutely legal for people to write unauthorized biographies, make documentaries or dramas about someone without needing their permission. You do not need permission to portray a real person in a work of art such as a book or movie - this happens all the time.

As for accuracy, in most countries you have recourse to the law if you think you have been libeled by someone in a work of art. However the level of proof and the necessity to demonstrate damage to your reputation may be high depending on the country you attempt to do this in - it is for example easier to claim libel in the UK compared to the USA. Freedom of speech is enshrined in law in many countries and works against rights to privacy or being libeled.

Finally it is often simply not worth fighting something like this, the negative publicity of trying to stifle the creator of a work of art can at times be considerable. Taking to the courts to defend your privacy can draw attention to your situation or your discomfort more .. see the Streisand Effect.

The fact that this book and the movie are about a lawsuit, would make any defamation claim that might be brought by Mark Z even bigger news - therefore likely to be worse publicity, even if he could prove libelous damage against him. Given that he is a very successful businessman, it is probably not worth his time and effort pursuing it.