Weibo, China's most popular micro-blogging site, is thriving but the CEO of parent firm Sina Corporation told CNBC he neglected investment in its core portal.
"There's no question that we have underinvested a little bit," said Chao.
"That's another reason we have [carried out a] separate listing for Weibo. Then people will go back and look at Sina with a clearer picture [and] without Weibo what does it look like?" he added.
Weibo - described as a hybrid of Twitter and Facebook - was spun off from internet portal Sina in March but raised a less-than-expected $286 million after the size of its IPO was reduced amid a selloff in technology shares in April.
Chao said the firm failed to invest enough in mobile, in particular.
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"It's [Sina's] portal and it has a lot of traffic and revenue growth and also good profit but it's true, we have not invested enough money in the mobile area," he added.