Google bought Motorola for $12.5bn only to sell it off for a paltry £2.9bn
This is misleading. When Google bought Moto, the price was due to a bidding war for access to Moto's patents. When Google sold Moto on, they did so without these patents, in other words, without the thing that made it worth $12.5bn. Don Harrison, Google's VP of M&A said:
I think the Motorola transaction has been a success for us. Financially, we bought the asset for $12.5 billion. It had $3 billion in cash; we were able to sell the Home division for $2.5 billion; we ended selling the handset division for $3 billion. There were some other tax assets as well. When you work through the math, you realize we spent between $2.5 billion and $3.5 billion for the patent assets. At the time, the nearest comparable transaction was the Nortel patent auction where Microsoft and Apple teamed up to buy that asset for $4.5 billion. And there’s a good argument that the Motorola patent portfolio is a better portfolio.