Famous search engine Yahoo Inc. have built a secret custom software program in 2015 that searches all of its users' new emails for very accurate information that is given by the US intelligence agencies.

The company obeyed the demand of the United States government by searching and scanning very specific information on hundreds of millions of Yahoo email worldwide, according to three former personnel of Yahoo and a fourth person who is included in the event, Reuters reported.

Experts would say that this is the primary case that reports an internet company obeying requests of the US government such as surveying all incoming messages, in contrast with checking out the already stored messages or through little amount of accounts at a time.

As of the moment, it is know what the US government is exactly looking for, but experts said that there are specific set of characters that the US government is trying to search for. Meaning, it could be a sentence, a phrase or even an email attachment according to unidentified sources.

According to the witnesses, the Chief Executive of the company, Marissa Mayer, is the one behind the decision of saying yes to the request of the US government to access some information on all its users' emails. Moreover, according to sources, she is behind the exiting of the company's Chief Information Security Officer Alex Stamos, who is now an employee at Facebook Inc.

However, Yahoo denied this accusation after Reuters reported the incident. Spokesperson of Yahoo sent a statement on TechRadar that news are misleading and that the company hardly says yes to requests of government for data. Furthermore, he stated that the software didn't exist in their company.

However, its somehow fascinating to notice that this spokesperson actually says that news are misleading and not necessarily wrong or false. Therefore, it is possible that there is a pinch of truth in the news however, Yahoo refuses to cooperate and report which part is correct.

Since Yahoo denied the accusations of having a software that scans emails, it could be very confusing why Yahoo have announced that it is a law-abiding company and its loyalty belongs to the government, and deny allegations the next day.