In a testament to TikTok’s (and perhaps the short format video) popularity, Tiger Global reportedly continued to build stake in TikTok parent Bytedance over the past 21 months. The rather sustained buying of shares by Tiger Global in secondary markets has continued, with Bytedance now being valued in the proximity of $90-$100 billion, says a new report from Financial Times (paywalled).

FT is citing an internal letter that the New York based investment firm sent to its investors. The letter stated that the firm had “purchased shares over the past 21 months at a low multiple of future free cash flow”. There was no disclosure on the size of the agreement as well as the valuation at which these share purchases were made.

However, Bytedance’s past fundraising activity does give a glimpse into what could be the company’s potential valuation. The TikTok parent’s most recent fundraise was in 2018, when the company galloped a massive $3 billion in a round led by Softbank. The $75 billion valuation in that round made Bytedance the second most valuable startup, behind Alibaba-owned Ant Financial.

The FT report, citing people aware of Tiger Global’s previous share purchase transactions, says that the firm started buying into Bytedance at half that valuation. The firm has further added to the position through purchases in secondary markets. More recently, Bytedance share trades in the secondary markets recently valued the company in the range of $90-$100 billion.

Tiger Global’s premise behind buying shares despite a rather steeply rising valuation, rests on Bytedance’s projections of commanding 19% of the advertising revenue this year. That would total to a staggering $81 billion, according to data captured by eMarketer.

This investor push into Bytedance, particularly from a US investment firm of the size of Tiger Global, comes amid rising concerns on TikTok’s handling of privacy, specially in the US. The app has faced continued scrutiny at multiple instances, most recent of which came when data of millions of users was left exposed by the app. A series of lapses were discovered in TikTok, which could have let hackers exploite or manipulate user account data.

Then prior to that, TikTok received a major setback in the US when it was banned by the country’s naval forces. Pentagon spokesman Lieutenant Colonel Uriah Orland said in a statement at that time, that the order was part of an effort to “address existing and emerging threats”. The US Navy issued orders, banning the installation of the short video app on devices of its personnel, violation of which would lead to a ban from the forces’ intranet. TikTok had earlier been temporarily banned by the Indian Government as well, which reportedly costed the app some 15 million users.

However, none of these security concerns have caused any dent in the app’s popularity whatsoever. TikTok has continued to grow exponentially, even more ballistically outside its home market China. The app recently made its debut into the top 10 most downloaded apps of 2019 on Apple’s App store, taking the 4th spot. This was above the likes of Facebook, Netflix and Gmail.