Looking on the internet deeply has found these results:

I'm in the company is the most popular phrase on the web.

I'm at the company 13 results on the web	I'm in the company 12,660,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I'm sure Jimmy would appreciate the company. I'm at the drug company, and the janitors are robbing the place. I wish I wish I could and make the money I'm making at the water company, but I can't. I told her to take it since I'm back at the company. You know, right now, I'm working at the same company with Nanami. I'm playing a match at the Company this weekend. I told her to take it since I'm back at the company.	I'm not interested in inheriting the company. I'm in the company's hands, now. I'm in the road company of 42nd Street. I'm used to being in the company of men. I'm in the main company system. I'd wager I'm in the company of visiting royalty. Yes, well, since Graham's unfortunate accident, I'm in charge of the company, so you can deal with me from now on. I'm in the company of two cruiser class vessels under the flag of the Mikkei Combine.

I'm at the company

13 results on the web

I'm in the company

12,660,000 results on the web

More popular!

I'm sure Jimmy would appreciate the company.
I'm at the drug company, and the janitors are robbing the place.
I wish
I wish I could and make the money I'm making at the water company, but I can't.
I told her to take it since I'm back at the company.
You know, right now, I'm working at the same company with Nanami.
I'm playing a match at the Company this weekend.
I told her to take it since I'm back at the company.

I'm not interested in inheriting the company.
I'm in the company's hands, now.
I'm in the road company of 42nd Street.
I'm used to being in the company of men.
I'm in the main company system.
I'd wager I'm in the company of visiting royalty.
Yes, well, since Graham's unfortunate accident, I'm in charge of the company, so you can deal with me from now on.
I'm in the company of two cruiser class vessels under the flag of the Mikkei Combine.