Usually the word who is only used (as a relative pronoun) for people. Things are usually referred to using the word that. However some teachers tell their students that it is always this way. There are some cases where it is not. Do organisations count as people or things? Sometimes this is a question of corporate law, here it is an issue of grammar and style-choice.
Companies, clubs, churches, cities and so on are groups of people. I have seen a company that was just a file of papers. It sat on the shelf, never did anything and was forgotten. It can't actually do anything. When a company makes a new telephone it is not the legal paperwork that does it, people make the new telephone. Whenever the company being described is referring to the actions of people it is better to use the word who instead of the word that.
The company, who operates nine customer service groups, realized annual productions of 158.56 million barrels of oil equivalent.
How do I prove to the High Court that the company who owes me money cannot pay its debts?
(UK Government, DETINI)
However many companies prefer to use the more impersonal word that when dealing with embarrassing topics.
The company that subcontracted its work to PZ was prompted by our findings to audit its other subcontractors for underage labor violations.
(Apple Inc. 2013)
The company did not do the subcontracting, but the manager. It would be more accurately written:
The manager who subcontracted work to PZ was prompted by our findings to audit his other subcontractors for underage labor violations.
However sometimes companies do things that people can't do, like be founded, sold or listed on the stock market. In these cases it is better to use the word that instead of the word who.
Las Vegas is the largest metropolitan city in the U.S. that was founded in the 20th century.
(Las Vegas City government)
It is worth noting that treating organisations, such as companies, as people applies to using the word who instead of the word that. These groups are still normally referred to as it and not he or she. However the word they can be used to refer to people in those organisations. The exceptions are that some countries traditionally have been referred to as he or she. However even in such cases using the word it is not an error, but a style choice.
Organisations are just pieces of legal paperwork and usually should be referred to using words like that and it. However it is your style choice to use words like who or they to refer to the people who do the organisation's work.
Next week I'll cover the use of whose for objects.