Globalisation poses a challenge for businesses with linguistically diverse staff, prompting the choice of English as the default corporate language. Although many studies extensively explored the role of corporate language policy in large corporations, employees' perceptions of such policy has not been explored adequately. Fewer studies investigate the trends in such perceptions in social media texts. This study fills this gap; it examines the barriers in multinational companies that have adopted a foreign language and analyses employees' attitudes. The study uses computer-assisted text analysis to investigate changes in employees' perceptions of an English-only policy in Rakuten, a Japanese company. It analyses a corpus of 704 social media posts on OpenWork from 2010 to 2018. The study finds some trends in employees' attitudes such as the inconsistency between expectation and reality in terms of 'Englishnization' and the popularity of the Test of English for International Communication (TOEIC). The findings suggest that Rakuten is not global in the true sense; the value of the TOEIC score is overestimated and the neoliberal employment system affects employees in complex ways. This study contributes to international business language with a bottom-up, employee-centred, and diachronic perspective on language management.