the whole company; company-wide
Refers to the entire single company or organization. Often used in business contexts for company-wide events, meetings, or policies.
The whole company is working on the new project.
There is a company-wide meeting tomorrow.
all companies; all firms
Refers to every company in a given context, such as an industry or market. Less common than the single-company sense.
This regulation affects all companies in the industry.
The whole company is introducing a new policy.
The whole company is tackling this problem together.
They announced the new policy to the whole company.
各社 means 'each individual company' in a group, while 全社 in this sense means 'all companies' viewed collectively as one whole.
社内 emphasizes something happening 'inside the company' (as opposed to outside), while 全社 emphasizes 'the whole company acting as one unit'.
all staff; all employees; entire workforce
Compound of 全 (zen, 'all') and 社 (sha, 'company'). A straightforward Sino-Japanese word.