The US tech titan said it will “move quickly” to re-engage with the social video app’s China-based parent company ByteDance with the aim of completing discussions no later than September 15.
This follows conversations between President Trump and Microsoft chief executive Satya Nadella.
“During this process, Microsoft looks forward to continuing dialogue with the United States Government, including with the President,” the company said in a blog post on Sunday.
Trump had on Friday said that he was planning to ban the Chinese video app over the weekend over data security concerns and amid tensions between Washington and Beijing.
TikTok has reportedly been in discussions with the UK government in recent months about potentially re-locating to London as part of a strategy to distance itself from China.
Microsoft, which said it may invite other US investors to participate on a minority basis in this purchase, added that it would add “world-class security, privacy, and digital safety protections” to the TikTok app.
The discussions have centred around its potential purchase of TikTok’s business in the US, Canada, Australia, and New Zealand.
“Among other measures, Microsoft would ensure that all private data of TikTok’s American users is transferred to and remains in the United States,” said the Windows software maker, whose acquisitions in recent years have included LinkedIn, GitHub and Minecraft.
A purchase price of US$30bn has been reported, which would top the US$26bn paid to acquire LinkedIn, but is a drop in the ocean of Microsoft's US$1.5trn market valuation and also less than the US$45bn of free cash flow the group generated in its past financial year.
Other investors in ByteDance were reported on Friday to be putting a potential bid for TikTok together, which put the valuation of around US$50bn.
Microsoft shares climbed another 4% to US$214.4 in early Wall Street trading on Monday, taking 12-month gains above 62%.
Analysts at UBS in New York said: "Microsoft's efforts in ad-supported consumer internet have been a mixed bag historically, and as a result we expect some investor skepticism regarding the proposed transaction.
"Microsoft has also managed to avoid some of the regulatory scrutiny facing other large-cap tech peers, so it comes as a bit of a surprise that the company would put itself in the spotlight by aiming to buy TikTok despite Trump administration concerns about ties to China.
"That said, Microsoft has had success in recent years taking an arms-length approach to acquisitions, with GitHub and LinkedIn retaining a fair degree of autonomy, which could help TikTok succeed where other Microsoft efforts in consumer internet have struggled.
"At the same time, even a relatively large amount paid for TikTok would be fairly small within the greater whole of Microsoft, limiting risk."
The analysts said the acquisition of TikTok might be of interest to Microsoft based on its interest in acquiring network businesses in the recent past, with TikTok likely to bring an expanded community into the broader Microsoft environment.
"Replatforming TikTok to Azure could also add a valuable proof point regarding the scalability and security of Azure. Finally, the success of TikTok could add a new front to Microsoft's competitive positioning vs. companies like Google, Facebook, and Amazon, which have strength in the consumer sphere and are increasingly encroaching on Microsoft's corporate stronghold."
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