A company can have many employees. Yet in law and in grammar it is a single entity.
You should always use singular verbs with companies, even when the company name sounds plural. The same applies to countries, political parties, governments and partnerships.
All are singular.
Some people think using they instead of it makes writing more personal. It can do. But that’s not the point.
Marketing departments like to describe companies as plural because they think that gives readers a point of connection. It makes us think we are dealing with human beings.
That may be true. Even if the company in question are a bunch of great people who really are fun to do business with, that’s not the point. It’s still a singular legal and grammatical entity. And anyway, we all know companies are staffed by humans.
Singular adds clarity
The problem here is that incorrect grammar makes your writing and, more important, your meaning, unclear.
There is another reason. If you read a company described as plural in print on a website, that’s a clear sign that the writer, editor or publisher is second-rate. Those of us who have worked for a long time in written communications know the writer or maybe whoever employed that writer, is unprofessional or, if that sounds too harsh, sloppy.
Most readers may not spot this as an error on a conscious level. Yet they know what professional writing looks like and many will subconsciously recognise the words in front of them are not professional, even if they can’t articulate why. They may have an inkling there is something wrong here.
When that happens they will be wary of what they read. Consciously or subconsciously they’ll think that if the writer doesn’t know enough to get simple grammar correct, it’s unlikely they did a professional job of fact-checking.
When you write they do you mean the company or all the people who work for the company? If you mean the employees, then make this clear. There’s nothing wrong with talking about, say, the staff at my local café.
Resist all temptation to treat companies as plurals. That goes for countries, political parties, governments and other organisations.