Chinese regulators announced on Friday a wide range of rules aimed at curbing spending and rewards that encourage video games, dealing a blow to the world's biggest games market, which returned to growth this year.

The new rules, which will effectively set spending limits for online games, sparked panic among investors, wiping off nearly $80 billion in market value from China's two biggest gaming companies, as investors sought to gauge the potential impact on earnings and more restrictions in the offing.

Online games will now be banned from giving players rewards if they log in every day, if they spend on the game for the first time or if they spend several times on the game consecutively. All are common incentive mechanisms in online games.

Shares in Tencent Holdings, the world's biggest gaming company, tumbled as much as 16% at one point, while those of its closest rival, NetEase, plunged as much as 25% after the National Press and Publication Administrations published the new draft rules.

Shares of Tech investor Prosus followed Tencent lower, losing 14.2% in early trade on Friday and among the biggest fallers on the pan-European stock index. It owns a 26% stake in Tencent.

"It's not necessarily the regulation itself - it's the policy risk that's too high," said Steven Leung, executive director of institutional sales at broker UOB Kay Hian in Hong Kong. "People had thought this kind of risk should have been over and had started to look at fundamentals again. It hurts confidence a lot."

Beijing has become increasingly tough on video games over the years. In 2021, China set strict playtime limits for players younger than 18 and suspended the approvals of new video games for about eight months, citing gaming addiction concerns.

Although the crackdown formally ended last year with the resumption of new game approvals, regulators have continued to dish out restrictions to curb "in-game" spending. The new rules revealed on Friday are the most explicit regulations yet aimed at curbing in-game spending. Besides banning reward features, games are also required to set limits on how much players can top up their digital wallets for in-game spending.

"The removal of these incentives is likely to reduce daily active users and in-app revenue, and could eventually force publishers to fundamentally overhaul their game design and monetisation strategies," said Ivan Su, an analyst at Morningstar.

Tencent and NetEase did not immediately reply to requests for comment.

An industry executive, who declined to be identified due to the sensitivity of the issue, said the new rules are not a new round of crackdown but in line with official efforts to promote a healthy gaming industry, adding the market has overreacted.

Games are also banned from offering probability-based lucky draw features to minors, and from enabling the speculation and auction of virtual gaming items.

But the new rules included a proposal that is widely expected to be welcomed by the industry, requiring regulators to process game approvals within 60 days. The new rules also reflects Beijing's concerns over user data, requiring game publishers to store their servers within China.

The administration is seeking public comment on the rules through Jan. 22, 2024. As a result of Beijing's crackdown on gaming in 2021, 2022 was the Chinese gaming industry's most difficult year on record as total revenue shrank for the first time. China's video game market returned to growth this year as domestic revenue rose 13% to 303 billion yuan ($42.6 billion), according to Industry association CGIGC.

New draft rules targeting in-game spending wipe billions from China’s tech giants.

Shares of several Chinese tech giants tanked in Hong Kong on Friday, wiping billions off their collective value, after Beijing unveiled a new set of regulations to restrict online spending in the gaming industry as part of its wider crackdown.

Tencent, one of the biggest gaming companies in the world, plummeted 12.4% on Friday in Hong Kong. It was the stock’s worst day since October 2008, during the depths of the global financial crisis.

The drop wiped 367 billion Hong Kong dollars ($47 billion) off Tencent’s market value, according to CNN calculation based on the stock market statistics.

NetEase, another gaming giant, dived 25% in Hong Kong afternoon trade, marking its biggest daily loss since it first listed there in June 2020.

That plunge wiped 128 billion Hong Kong dollars ($16.4 billion) in value.

Bilibili, one of China’s biggest video-sharing platforms, plunged 9.7%. Kuaishou, operator of China’s second-largest short-video app, fell 7.2%. Both companies have businesses in online gaming.

The proposed draft also stipulated that in-game measures that could lead to trading of virtual goods at a high price — such as auctions — will be prohibited, adding that large tips to players who livestream their games will also be banned.

Games should only offer real name registration to players, and game publishers should store data locally, according to the draft rule.

In-game purchases have become ubiquitous and highly lucrative within the gaming sector, particularly for mobile games which are often released to consumers for free.

The move comes as China intensifies its crackdown on its massive online gaming industry, as Beijing seeks to reverse what it sees as a growing trend of gaming addiction among young people.

In August 2021, China barred online gamers under the age of 18 from playing on weekdays and limited their play to just three hours most weekends.

That was part of Beijing’s sweeping clampdown targeting what it sees as overly powerful companies, especially in Big Tech. The regulatory onslaught, which started in late 2020, has shed more than $1 trillion in market value from the Chinese companies worldwide and sent chills through the wider economy.

But as China’s economic outlook deteriorates, Beijing has shown signs of easing the crackdown, frequently talking up tech companies’ role in the economy.

Before Friday’s sell off, Tencent had rebounded 64% from its historic low on October 28, 2022.