US online social media giant Twitter is considering legal action against Meta (formerly Facebook) over its fast-growing rival app Threads, which launched this week.

Threads, which launched to millions on Wednesday, is similar to Twitter and has been touted by Meta bosses as a “user-friendly” alternative.

Twitter’s Elon Musk said “competition is good, cheating is not”. But Meta denied allegations in a legal letter that former Twitter staff helped set up Threads.

Of South African descent, the man considered the richest in the world, with an estimated net worth of around US$251.1 billion as of July 6, 2023, spent $44 billion to buy Twitter.

More than 30 million people have signed up for the new app, according to Meta. That’s less than a tenth of Twitter’s estimated 350 million users, according to Statista.

It is reported that it took four years for Twitter to have the same number of users that Threads gained in one day. Although Twitter grew its user base from scratch, Threads was able to tap into the pre-existing two billion monthly users.

Experts say that US copyright law doesn’t protect ideas, so for Twitter to succeed in court, it would have to prove that its own intellectual property, such as programming code, was taken.