Hello folks,
I have scavaged through this forum for this important questions but could not find a satisfactory answer.

I am a blue card holder for last 1 year or so. My wife recently got a job offer in Berlin. Her residence permit with 'erwerbstätigkeit gestattet' allows her to work without restrictions. Her salary is about 36K which means she doesn't qualify for her own blue card (i guess?).

My question is:
- Does she need to inform the ausländerbehörde that she got a job? Does she need to update her residence permit or something?

Thanks in advance

Yes of course. She has to inform and get either a work permit or blue card from ABH based on the eligibility. This is because of her separate contributions to pension funds and health insurance premiums. 

Thank you! with her salary of 36K it won't be possible for her to get a Blue card. What kind of work permit can she apply for? Is there a vague possibility that she gets denied?

Additionally will she have to go through a 'vorrangprüfung'?

General question: what is the meaning/purpose of  giving her this 'erwerbstätigkeit gestattet'  when she has to go through the process of applying for a work permit again? 

I have found this additional information just to confuse myself further:

http://www.jena.de/de/stadt_verwaltung/stadtverwaltung/dezernat2/fd_personen_aufenthalt/auslaenderbehoerde/erwerbstaetigkeit/225422

Infos zur Erwerbstätigkeit während des AufenthaltsSeit 2005 werden von der Bundesagentur für Arbeit für Arbeitnehmer keine gesonderten Arbeitsgenehmigungen mehr ausgestellt. Ob eine Erwerbstätigkeit erlaubt ist, ergibt sich bereits aus dem ausländerrechtlichen Aufenthaltstitel.Jeder Aufenthaltstitel muss deshalb erkennen lassen, ob die Ausübung einer Erwerbstätigkeit erlaubt ist.

Angaben zu Erwerbstätigkeit finden sich direkt im AufenthaltstitelLautet der Eintrag im Aufenthaltstitel "Erwerbstätigkeit gestattet" ist jegliche Erwerbstätigkeit erlaubt. Erwerbstätigkeit ist die selbständige Tätigkeit und die unselbständige Beschäftigung.

It seems to me that after 2005 there no need of additional work permits. However your assertive ''Yes of course. She has to inform and get either a work permit or blue card from ABH based on the eligibility. .. " indicate that i might be wrong.

It seems you are confused and trying to confuse us too. The process is clear and simple. With "Erwerbstätigkeit gestattet" mentioned on your RP does not mean that you should not inform ABH. Also before BC, we had normal work permits and your wife will get one such. She may or may not go through  'vorrangprüfung'.

The main reasons of informing ABH are to change the status of visa from dependent to WP for easy extensions, changing tax class which will eventually influence social contributions from you as well as BA für Arbeit in the case of unemployment. 

Thank you for your answer. What factors are considered while issuing such work permits? Could her low salary be a problem? Does salary or any other restrictions apply for spouse work permits?

Apologies for this bombardment of questions but we are bit nervous about all this.

I would say there are many factors. However, in her case, it will be simple and straight forward. Since she is dependant the normal WP can be given even she has a contract with a minimum (~9€ per hour) salary. So without worries let her process work permit and come back to us with all positive updates.

- Does she need to inform the ausländerbehörde that she got a job? 
Yes, she should inform Ausländerbehörde.

- Does she need to update her residence permit or something?
Most probably they gonna keep the same as before.

- Is there a vague possibility that she gets denied? Could her low salary be a problem?
As you are a blue card holder, chill out. She has more freedom in job requirements than you.
No chance of being denied I would say. Job just have to fulfill minimum salary and work conditions.

PS: go to Finanzamt and inform them the situation. Check the possibities to change her Steuerklasse.

From my own experience, Erwerbstätigkeit gestattet implies that no prior permission is required from the Ausländerbehörde.
My wife has it on her residence permit and she did not need to inform anywhere when she took up a job here. Even when she later went to renew her permit, the people there weren't bother that she was working already.

My understanding from what others before me have mentioned is that you need to get a permission from Ausländerbehörde IF your wife no longer wants to be on a dependent status and wants to change the residence permit to a fully independent one. In that case, it is then treated as a fresh application for Work permit.

Thanks you guys for your inputs.

I have been asking around on this and judging from the 'own experience' guys my wife probably does not need to do anything if she want to stay dependent, which makes sense since she does not qualify for a blue card yet. I have no clue about the requirements of a normal 'pre blue card' work permit.

I am reluctant to contact the Ausländerbehörde because in my experience their decisions are so subjective that we might end up entangling ourselves in some unneccessary crap. Maybe we will try contact them just for sake of clarity.