> **Possible Duplicate:**  
> [Sentences using: \[something\] + have + they](https://english.stackexchange.com/questions/62208/sentences-using-something-have-they)  
> [subject-auxiliary inversions not associated with questions](https://english.stackexchange.com/questions/80644/subject-auxiliary-inversions-not-associated-with-questions)  

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In the following, why does subject-verb inversion occur? Is it necessary? And what is this type of inversion called? 

Colleague’s original:
> Only in cases where A is B, the Company shall do X.

I changed to the following:
> Only in cases where A is B shall the Company do X. 

Searching Google for “shall the Company” gives examples such as:

> In no event shall the Company ...  
> Under no circumstances shall the Company ... 

And these all seem quite natural. 

“In no event” and “under no circumstances” seem to be prepositional phrases, yet I would say simply, with no inversion:

> In the fridge, you will find some beer. 

Is the S-V inversion maybe some sort of archaic style that remains in legal or maybe religious texts? Perhaps a remaining German-style syntax?