First TikTok, now Pinterest. Whoever is in charge of Microsoft’s acquisition strategy appears to be an ardent social media fan. What next — Clubhouse?

Microsoft’s interest in Pinterest is hard to fathom. With $132bn in cash and short-term investments, it could comfortably afford to make an all-cash offer for the social network, which has a $49bn enterprise value. But why would it want to? Microsoft is best known for workplace tools and cloud computing. It is difficult to see where an image-based platform known for aspirational vision boards and biscuit recipes slots in.

Admittedly, Microsoft has made one major social media purchase before: workplace networking site LinkedIn. But that $26bn, all-cash acquisition was aligned with Microsoft products like Office 365. Pinterest is not only disconnected from Microsoft’s existing business it is also pricey. Its share price has more than tripled in the past 12 months. LinkedIn was valued at 55 times forward ebitda when it was purchased in 2016. Pinterest is valued at 81 times, using S&P Global data.

Chart shows % US social media users showing Pinterest is popular across multiple generations

This is down to Pinterest’s recent rise in user and revenue growth. If revenue continues to tick up at the same pace it might be reporting $4bn in annual sales by 2023. Average revenue per user rose nearly a third in the past year to $1.57. But it is worth noting how puny this figure is. Facebook’s ARPU is over $10. Pinterest’s journey towards monetisation has been slow. It has yet to report a full year of operating profit.

The good news is there is plenty of room left to grow in the US — the most lucrative region for advertising and one where social media giant Facebook struggles to find new users. Of 459m monthly Pinterest users, only a fifth are based in the US.

Microsoft needs more fodder for its Teams and Azure cloud computing products. This was put forward as an explanation for its interest in TikTok. It may also be looking for more information to develop data analysis services and a way to build its advertising business. But buying Pinterest would be an expensive way to go about it.

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