BEIJING, China — Two of China's richest men are intensifying their rivalry over the world's biggest Internet market.

Jack Ma's Alibaba Group Holding Ltd., the country's largest e-commerce company, on Aug. 1 said it blocked Tencent Holdings Ltd.'s WeChat to sellers. Four days later, billionaire Pony Ma's Tencent introduced online payment features to mainland China users of its WhatsApp-like chat software.

Alibaba is headed for what may be the biggest initial share sale since Facebook Inc., while Tencent is China's biggest Internet company, with more than 300 million users for WeChat, which started in 2011. Both have made purchases and encroached on each other's established markets in the battle for dominance of the country's online spending. McKinsey & Co. estimates China's Internet retail will triple to $395 billion from 2011 to 2015.

“Tencent is still in the land-grabbing phase,” said Billy Leung, an analyst at RHB Research Institute Sdn. in Hong Kong. “They’re still trying to improve their market share for the e- commerce space. On the other hand, Alibaba is trying to defend its territory.”

Tencent has surged 51 percent this year, the most on Hong Kong’s benchmark Hang Seng Index and pushing its market value to almost $90 billion. Alibaba’s valuation may be about $105 billion should it push forward with an IPO, Goldman Sachs Group Inc. estimated in a July 22 report.

Net Worth

Jack Ma, founder and chairman of the company whose Taobao Marketplace beat EBay Inc. in China, has a net worth of $3.6 billion, according to data compiled by Bloomberg. Tencent Chairman Pony Ma is worth $9.6 billion, the data show. The two men are unrelated.

Alibaba, which also owns Tmall.com, China’s top business- to-consumer website, on Aug. 1 said it disabled sellers’ access to WeChat because of security reasons. Virtual shoppers were offered the option of logging on to Alibaba’s Taobao site using their Sina Corp. Weibo accounts, which are microblogs similar to Twitter Inc.’s social media platform.

Closely held Alibaba had in April agreed to buy a stake in Sina’s Weibo business, China’s biggest microblog.

Ma, a former English teacher, is also expanding into financial services, logistics and delivery networks and smart TV. Alipay.com Co. is offering services to fund companies in China. The electronic-payments operator reached agreements with 37 companies, with varying forms of cooperation, Florence Shih, a spokeswoman at Alibaba, said in an Aug. 5 e-mail.

Wealth Management

Tencent, meanwhile, has agreed to offer online payment services to 10 Chinese fund companies, according to a July filing with China’s securities regulator. It also tied up with Beijing-based China Asset Management Co. this month to offer wealth management services to WeChat users.

Alibaba’s Ma has made other acquisitions. The e-commerce group on May 10 announced the $294 million purchase of 28 percent of Beijing-based mapping company AutoNavi Holdings Ltd.

Alibaba hasn’t kept up with Tencent’s WeChat in mobile development, Ma said in March, even though his company started developing its mobile business three years ago.

More than 84 percent of China’s Internet users regularly access instant messaging, making it the most popular online application in the country, followed by search engines with about 80 percent, according to data compiled by Bloomberg.

Gaming Lead

About 76.5 percent of Sina Weibo’s 49.8 million daily active users in March accessed the service through mobile devices, according to an earnings call in May.

Sina Weibo also began providing special designed pages for some Alibaba sellers on Aug. 5 to promote their products on the microblog, according to a joint statement from the companies.

Tencent will probably focus on using its advantage in gaming and developing related services on mobile platforms, while Alibaba will be more focused on e-commerce, said Alex Wang, a Beijing-based analyst at Internet consulting group IResearch.

Alibaba, which started as a business-to-business marketplace, has turned into a more consumer-focused operation getting most of its growth selling to individuals across the world’s most populous nation. To improve deliveries, it joined with five companies and other partners to found Cainiao Internet Technology Ltd., aiming to help establish a network that can reach any place in China within 24 hours.

Richest People

Alibaba in May also said it partnered with Qihoo 360 Technology Co. for an e-commerce search engine. It will compete against Baidu Inc., owner of China’s largest search engine.

Baidu Chairman Robin Li, worth $9.8 billion, and Pony Ma are China’s richest people after Hangzhou Wahaha Group Co. Chairman Zong Qinghou, who has $11.4 billion, according to the Bloomberg Billionaires Index.

Tencent may find itself in direct competition with Alibaba when developing location-based services such as helping mobile users find restaurants and shops, said IResearch’s Wang.

“I think Alibaba has the greater chance of winning” in location-based e-commerce, said Wang. “Alibaba has a lot of ammunition for payment systems, marketing and user base.”

Tencent made more than half of its 44 billion yuan ($7 billion) revenue last year from gaming. In the first quarter of this year as many as 15.6 million users were online simultaneously playing its games, including “League of Legends,” a real-time strategy game developed by U.S.-based Riot Games Inc., which is majority-owned by Pony Ma's company.

Tencent last month announced plans to buy 15.39 percent of gaming company Activision Blizzard Inc., owner of the hit titles “Call of Duty” and “World of Warcraft.” It bought a 13.8 percent stake of Korean messaging app company Kakao Corp.in April 2012, according to its annual report.

Tencent’s net income has surged eightfold in the five years through 2012 to 12.7 billion yuan on sales that grew 11-fold, according to data compiled by Bloomberg. The company had cash and short-term investments of 30.5 billion yuan as of March and its return on invested capital last year was 26.27 percent, compared with 27.37 percent in 2011.

By: Lulu Yilun Chen; Editors: Frank Longid, Suresh Seshadri