If memory serves me well, in one of the letters he sent a number of years back (10-ish?), he mentioned that they had someone in their staff managing a portfolio of stock picks and doing a great job at it, and gave a heads up to readers that they might find tech stocks come in and out of their portfolio every so often as a result. Presumably he liked the returns he was seeing and jumped in too.

Also, Apple displays a number of characteristics that he reportedly likes to invest in: the business that Apple is in is straightforward to understand, the market is big and they've a strong or growing market position, they're profitable and have a big cash position, they've a strong brand and difficult to reproduce expertise (i.e. a moat).

Yes, this always struck me as strange and at the time my naive thought was that Apple was overvalued.

https://www.youtube.com/watch?v=lTd7Iax-I60

What he says around 00:27 about Snickers applies very much to Apple as a brand. This is the only Buffet-ish explanation of why Berkshire would invest in Apple that I could think of.

And apart from this, the decision to buy a lot of Apple stock a while back was made by other asset managers, not Warren himself, and I'm sure was the result of thorough analysis, not based on some offhand comment in an interview.

A couple of possible points on that. Buffett is always learning and maybe he feel's he understands Apple enough now.

Also to quote Buffett "If you look at Apple, I think it earns almost twice as much as the second most profitable company in the United States". Which I guess attracts him - he's always been into consistent profits on modest capital which Apple is good at.

He also said somewhere that a person's "circle of competence" can grow as you learn.

That being said, lot of Berkshire's bets are now coming from Berkshire's next generation of managers - Ajit Jain, Greg Abel, Todd Combs and Ted Welscher. It is speculated that the decision to buy Oracle has come from either Todd Combs or Ted Welscher.

Todd Combs is also said to be driving Berkshire's investment into Paytm, an Indian e-wallet company which again is a technology company.

He says he sold off Oracle for precisely that reason.

2015 called