Facebook is the world’s largest social network. They earned about $17 billion in revenue. Their market capitalization is $360 billion.
Ernst & Young has been Facebook’s auditor since they went public in 2007. As you can see, the fee is relatively low similar to what Amazon pays. Fees aren’t necessarily based on the size of the company. They are based on the complexity of the audit.
You can see that EY has a sizable fee related to tax projects on Facebook. This often happens with young companies. As companies grow and acquire other companies, they face more tax compliance obligations than they were expecting. They then need help with those obligations and utilize the big 4 public accounting firms for that assistance.