Malaysia’s state-owned investment fund, 1MDB, was supposed to attract foreign investment. Instead, it has spurred criminal and regulatory investigations around the world that have cast an unflattering spotlight on financial deal-making, election spending and political patronage under Prime Minister Najib Razak. A Malaysian parliamentary committee identified at least $4.2 billion in irregular transactions.

1. What is 1MDB?

It’s a government investment company — full name, 1Malaysia Development Berhad — that took shape in 2009 under Najib, who went on to lead its advisory board. Its early initiatives included buying privately owned power plants and planning a new financial district in Kuala Lumpur. The fund proved better at borrowing — it accumulated $12 billion in debt — than at luring large-scale investment.

2. What’s the issue?

Investigators have been trying to trace whether money flowed through and around 1MDB and illegally into personal accounts. Some of the money is alleged to have ended up with Najib and his family. That includes $681 million that landed in the prime minister’s personal bank account, according to U.S. prosecutors. Malaysia’s attorney general, backed by Saudi authorities, said the $681 million was a donation from the Saudi Arabian royal family, much of which was returned. The U.S. Justice Department says the money instead came from, and was returned to, an offshore entity called Tanore Finance Corp. Another $700 million in 1MDB funds meant for a joint venture with a company known as PetroSaudi International was found to have landed in an unrelated offshore account. Najib has denied wrongdoing.